rename configure.in to configure.ac

Autoconf has been deprecating configure.in for quite a long time.
Rename all our configure.in and preconfigure.in files to .ac.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Fix ChangeLog formatting issue
Add missing bug number to NEWS
Add ChangeLog entry and fix NEWS for #16078
Fix reads for sizes larger than INT_MAX in AF_INET lookup

Currently for AF_INET lookups from the hosts file, buffer sizes larger
than INT_MAX silently overflow and may result in access beyond bounds
of a buffer.  This happens when the number of results in an AF_INET
lookup in /etc/hosts are very large.

There are two aspects to the problem.  One problem is that the size
computed from the buffer size is stored into an int, which results in
overflow for large sizes.  Additionally, even if this size was
expanded, the function used to read content into the buffer (fgets)
accepts only int sizes.  As a result, the fix is to have a function
wrap around fgets that calls it multiple times with int sizes if
necessary.
Remove code from div that is by C99 obsolete. Fixes bug 15799
Use atomic operations to track memory. Fixes bug 11087
malloc: Fix for infinite loop in memalign/posix_memalign.

A very large alignment argument passed to mealign/posix_memalign
causes _int_memalign to enter an infinite loop. Limit the maximum
alignment value to the maximum representable power of two to
prevent this from happening.

Changelog:

2013-10-30  Will Newton  <will.newton@linaro.org>

	[BZ #16038]
	* malloc/hooks.c (memalign_check): Limit alignment to the
	maximum representable power of two.
	* malloc/malloc.c (__libc_memalign): Likewise.
	* malloc/tst-memalign.c (do_test): Add test for very
	large alignment values.
	* malloc/tst-posix_memalign.c (do_test): Likewise.
Accept make versions 4.0 and greater