Import statements sorted with isort and fixed MockBuilder.py (#266)

* Fixed missing closing bracket in the MockBuilder.py

* Import statements sorted with isort

DependencyAnalyzer: Catch a non-existant system_packages_directory

* When run on non-haiku platforms, trying to analyze dependencies
fails with a python missing /boot/system/packages error.
* Catches that problem and ignores it with a warning.
* This lets the dump dependency code run on Linux
with an obvious long list of missing "haiku, haiku_devel"
dependencies

python3: Fix missed itervalues -> values

python3: Finish python3 change. python2 breaking

* Based on mmlr's 2017 work to use Python3 with
changes and adjustments for the current codebase

python3: begin python3 fixes. print -> print()

Cleanup: Make some constructs more idiomatic.

* Change 'not x in y' to 'x not in y'.
* Use 'is' to compare None singleton.
* Use 'instanceof(x, y)' instead of 'type(x) == y'.
* Replace map builtin with list comprehension.
* Rename self argument to cls for static method.

Cleanup: Remove trailing semicolons and a unneeded pass.

Cleanup: Whitespace and line length cleanup.

Port: Rework configuration of repository dir.

Use a class variable and a setter to make the repository dir known to
Port and add a context manager for temporarily adjusting the repository
dir of specific ports.

This removes the need to hand in the repository dir to various methods,
which makes things more consistent. Some methods were previously using
the repository dir given to the constructor while others needed it as
argument.

The Repository now makes itself known to Port and can change the current
repository dir for the purpose of populating a new repository at a
different path.

With this, the ugly manual adjustment of the recipe cache of the Port by
the Repository can be removed. It was directly changing internals of
Port but used slightly different logic than within Port which lead to
two different filenames being used for the recipe cache file. This
caused recipes to be parsed once unnecessarily.

Use Unicode strings for warn() & sysExit().

DependencyAnalyzer: Cleanup, remove unneeded variable.

DependencyAnalyzer: Also resolve requires of system packages.

This allows to find a set of bootstrap packages that need to be provided
in order build the other (cyclic) ports.

DependencyAnalyzer: Include more info in unresolved message.

When a require can't be resolved, also print which package and port
the requires originated from. This makes finding and fixing typos in
recipes easier.

DependencyAnalyzer: Sort printed dependency lists.

DependencyAnalyzer: Enumerate only active ports.

DependencyAnalyzer: Respect noSystemPackages option.

ShellScriptlets: Internalize parsing of scriptlet prerequires.

Reduces duplication and knowledge of the original format.

Adjust DependencyAnalyzer to new dependency resolution.

Refactoring: use properties where it seems fit.

* Trying to be somewhat more Pythonic.

Revert to tab spacing for Pe's sake.

Try again with whitespace.

Second attempt to fix whitespace. Options are different on OS X.

Convert tabs to spaces.

Cleanup: drop now superfluous method call.

Simplify conversion from package-name/ID to port-name/ID.

* adjust getPortIdForPackageId() and getPortNameForPackageName()
to check if the given parameter is already valid, simplifying
the loop, too
* drop explicit checks before invocation of getPortIdForPackageId()

Print resolving information during --do-bootstrap

* this should make it easier to debug any problems that may occur
when trying to untangle the circular dependencies

/boot/common has been removed

Mostly the changes are straight-forward (don't look in /boot/common,
adjust paths). A notable change concerns the resolution of port
dependencies: We no longer simply include all /boot/system packages in
the chroot, but only those that have to be pulled in according to the
dependency resolution. This may break some recipes that don't declare
all the things they actually require for building, but have worked
previously due to those dependencies living in /boot/system.

Adjust DependencyAnalyzer.getBuildOrderForBootstrap():

* don't pollute each port's work folder with package info files,
but use a temporary folder instead
* sort the list of immediately buildable ports by name, to get a
reproducable order (not a more or less random one)

Add DependencyAnalyzer.getBuildOrderForBootstrap():

* loop over ports with cyclic dependencies and try to find at least
one that is immediately buildable
* if a immediately buildable port has been found, pretend it has
been built and remove it from the set of cyclic dependencies
* complain if no port in the set is immediatly buildable (this means
that something is wrong in the declaration of requires or a
prerequired package is missing)
* continue until all ports have been handled

Restructure DependencyAnalyzer a bit.

* let __init__ only compute the different groups of nodes and print
them in printDependencies()
* keep full set of ports with cyclic dependencies (i.e. do not leave
out ports required by HaikuPorter directly)

Unifiy the Options and GlobalConfig somewhat

* Module GlobalConfig is replaced with new module Configuration. The
global variable globalConfiguration is gone. Instead Configuration
provides getter methods.
* For several of the (newer) command line options there are now optional
configuration file entries. If given the command line values override
the configuration file values. Configuration also provides getter
methods for these options, which should be used instead of
getOption().

Add option '--command-package' to specify the package command

Add license header (MIT)

* additionally: uppercase copyright notices and separate them from the
top by a single line

DependencyAnalyzer: Make repository directories subdirectories

... of the repository directory to keep things tidier.

DependencyAnalyzer: Consider haikuporter dependencies

Also:
* Remove special handling of self-depending ports. As done it wasn't
correct.
* Compute out-degrees and remove the acyclic part of the graph that
doesn't depend on anything else. ATM it is empty, though.

Thinking a while about it, for a correct analysis we need separated
build pre-/requires declarations for build host and target. Otherwise
it isn't clear what we actually need to cross-build a port.

DependencyAnalyzer: Discriminate between ports and packages

Now we correctly take the requires declarations into account.

Minor cleanup of imports

Add option -D for analyzing port dependencies

Currently it only prints the required system packages, the
self-depending ports, and the ports with cyclic dependencies.

Adjust DependencyAnalyzer to new dependency resolution.

Refactoring: use properties where it seems fit.

* Trying to be somewhat more Pythonic.

Revert to tab spacing for Pe's sake.

Try again with whitespace.

Second attempt to fix whitespace. Options are different on OS X.

Convert tabs to spaces.

Cleanup: drop now superfluous method call.

Simplify conversion from package-name/ID to port-name/ID.

* adjust getPortIdForPackageId() and getPortNameForPackageName()
to check if the given parameter is already valid, simplifying
the loop, too
* drop explicit checks before invocation of getPortIdForPackageId()

Print resolving information during --do-bootstrap

* this should make it easier to debug any problems that may occur
when trying to untangle the circular dependencies

/boot/common has been removed

Mostly the changes are straight-forward (don't look in /boot/common,
adjust paths). A notable change concerns the resolution of port
dependencies: We no longer simply include all /boot/system packages in
the chroot, but only those that have to be pulled in according to the
dependency resolution. This may break some recipes that don't declare
all the things they actually require for building, but have worked
previously due to those dependencies living in /boot/system.

Adjust DependencyAnalyzer.getBuildOrderForBootstrap():

* don't pollute each port's work folder with package info files,
but use a temporary folder instead
* sort the list of immediately buildable ports by name, to get a
reproducable order (not a more or less random one)

Add DependencyAnalyzer.getBuildOrderForBootstrap():

* loop over ports with cyclic dependencies and try to find at least
one that is immediately buildable
* if a immediately buildable port has been found, pretend it has
been built and remove it from the set of cyclic dependencies
* complain if no port in the set is immediatly buildable (this means
that something is wrong in the declaration of requires or a
prerequired package is missing)
* continue until all ports have been handled

Restructure DependencyAnalyzer a bit.

* let __init__ only compute the different groups of nodes and print
them in printDependencies()
* keep full set of ports with cyclic dependencies (i.e. do not leave
out ports required by HaikuPorter directly)

Unifiy the Options and GlobalConfig somewhat

* Module GlobalConfig is replaced with new module Configuration. The
global variable globalConfiguration is gone. Instead Configuration
provides getter methods.
* For several of the (newer) command line options there are now optional
configuration file entries. If given the command line values override
the configuration file values. Configuration also provides getter
methods for these options, which should be used instead of
getOption().

Add option '--command-package' to specify the package command

Add license header (MIT)

* additionally: uppercase copyright notices and separate them from the
top by a single line

DependencyAnalyzer: Make repository directories subdirectories

... of the repository directory to keep things tidier.

DependencyAnalyzer: Consider haikuporter dependencies

Also:
* Remove special handling of self-depending ports. As done it wasn't
correct.
* Compute out-degrees and remove the acyclic part of the graph that
doesn't depend on anything else. ATM it is empty, though.

Thinking a while about it, for a correct analysis we need separated
build pre-/requires declarations for build host and target. Otherwise
it isn't clear what we actually need to cross-build a port.

DependencyAnalyzer: Discriminate between ports and packages

Now we correctly take the requires declarations into account.

Minor cleanup of imports

Add option -D for analyzing port dependencies

Currently it only prints the required system packages, the
self-depending ports, and the ports with cyclic dependencies.