Rework and simplify string argument parsing. All string arguments are at
most DPISTRLEN (32) characters so there is no need for fancy dynamic
growing strings. Use a DPISTRLEN long buffer and bail if it fills up.

Rename get_string() to get_dpistr() and get_string_argument() to
get_dpstr_argument() to emphasize they will return strings that fit
in DPISTRLEN.

Rework & simplify a pair of their consumers - do_rename_partition() and
do_change_type() - to be more obviously identitical to each other bar
the displayed verbiage.

Whitespace fixes.

No need for 'default_value' parameter for get_number_argument() since we
always pass kDefault. a.k.a. -1. Nuke kDefault since it is now unused.

Nuke unused #define MAXIOSIZE in passing.

No need for get_string_argument() parameter 'reprompt' since we
always pass it '1'.

Hoist all file opening and ioctl calls into main(), passing a pointer to
a valid map to edit(). Should enable pledging a la fdisk at some point.

Since edit() always gets a valid map (and maintains its validity even when
'I'nitializing a new one) many checks for (map == NULL) are junked.

Remove some dances around block sizes by using DEV_BSIZE everywhere
since we don't support non-DEV_BSIZE (a.k.a. 512-byte) sectors.

Remove many superfluous #include statements.

Change "//" comments to "/**/". Nuke really stupid ones.

Reduce namespace pollution by eliminating parameter names from forward
declarations.

Remove a bunch of ridiculous and uninformative comments like "// Defines".

add rcs ids

update for pdisk 0.8a2, from NetBSD, retaining our local changes;
summing it up:

- Clean up sources - fix naming, delete old email addresses
- Added support for display of Mac volume names
- Fix block 0 display to show logical offset of drivers
- Require confirmation of quit without write
- Fix iteration to not complain about missing devices
- Warn when creating/writing a map with more than 15 entries

and, most important, add do_update_dpme() which allows us to partition
OpenBSD slices without previous MacOS setup.

Tested with shared MacOS install on macppc, procedure there remains the
same.

grammer and spelling help and ok jmc@

ok miod@

rm trailing whitespace

branches: 1.1.1;
Initial revision