Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Make the ArgArray_Init() function visible to the rest of make.
It will soon be needed for the .SHELL parsing code.

Get rid of global variables for argument vectors produced by brk_string()
introduce a struct that holds all the information about an argument
vector and pass that around.

Author: Max Okumoto <okumoto@ucsd.edu>
Obtained from: DragonFlyBSD

Move the Boolean and ReturnStatus stuff from sprite.h to util.h and
get rid of sprite.h.

Obtained from: DragonFlyBSD

Constify the input argument to brk_string.

Patch: 7.106

Submitted by: Max Okumoto <okumoto@ucsd.edu>

Convert several typedefs from beeing pointers to structs to be the structs
itself. This will ease constification (think of what 'const Ptr foo'
means if Ptr is a pointer to a struct).

Submitted by: Max Okumoto <okumoto@ucsd.edu>

Clean up include files and file including. Split nonints.h into pieces
that get included just where they are needed. All headers include the
headers that they need to compile (just with an empty .c file). Sort
includes alphabetically where apropriate and fix some duplicate commenting
for struct Job, struct GNode and struct Shell by removing one version and
inlining the comments into the structure declaration (the comments have been
somewhat outdated).

This patch does not contain functional changes (checked with md5).

Submitted by: Max Okumoto <okumoto@ucsd.edu>