- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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

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

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

In reallocf(3), free the memory only when size != 0. Otherwise, when the
System V compatibility option (malloc "V" flag) is in effect a zero sized
reallocf() could cause a double free.

PR: bin/141753
Submitted by: Dan Lukes

Fix the style of the SCM ID's.
I believe have made all of libc .c's as consistent as possible.

$Id$ -> $FreeBSD$

Fix style problems noted by Bruce:
o No copyright on reallocf.
o Order makefile list correctly.
o indent reallocf properly.

Add reallocf to the library. This function is simliar to realloc, but
when it returns NULL to indicate failure, it will also free the memory
that was passed to it, if that was non-null.

This does not change the semantics of realloc.

A second commit will be done to commit the conversion of those places in
the code that can safely use this to avoid memory leaks when confronted
with low memory situations.

Beaten-to-death-but-finally-approved-in: -current