refdb: fix typo and wording
zstream: grow based on used memory rather than allocated

When deflating data, we might need to grow the buffer. Currently we
add a guess on top of the currently-allocated buffer size.

When we re-use the buffer, it already has some memory allocated; adding
to that means that we always grow the buffer regardless of how much we
need to use.

Instead, increase on top of the currently-used size. This still leaves
us with the allocated size of the largest object we compress, but it's a
minor pain compared to unbounded growth.

This fixes #2285.
pack-objects: always write out the status in write_one()

Make sure we set the output parameter to a value.
Merge pull request #2301 from libgit2/cmn/pack-objects-memory

Keep the deflate buffer from ballooning up
Make the build CMake 2.6 compatible
Merge pull request #2306 from odcinek/development_cmake

Make the build CMake 2.6 compatible
MidnightBSD may also not have strnlen
Merge pull request #2309 from jacquesg/midnightbsd

MidnightBSD may also not have strnlen
Unquiet CMake output

The point of this phase is to know what we have and not. Show the user a
clear indication of what we have.
Workaround missing .pc files on FreeBSD

This fixes #2118
Don't exclude libssh2 from MinGW

It reportedly works. It does not however work when cross-compiling on
Travis, so let's disable it there.

This fixes #2311.
refs: document _next_name()

If it's not documented, it doesn't show up in the docs (and we really
should document, anyway).
ciscript: don't use an empty string as a number

An empty string is not a valid number, and some shells complain.

Check instead if $COVERITY is non-empty, which is a common convention
and what we're doing anyway.
cygwin also doesn't have qsort_r
Merge pull request #2315 from jacquesg/qsort-cygwin

cygwin also doesn't have qsort_r
Merge pull request #2314 from libgit2/cmn/known-libs

Assorted CMake fixups
Build regex.c for Solaris. Added required defines for Solaris
strcasecmp is in <strings.h>
Check for NULL before passing it to vsnprintf
Merge pull request #2304 from jacquesg/solaris

Solaris!