. GD is now thread-safe thanks to wrappers around freetype library
. Significant optimization to png writing code.
. Miscellaneous fixes.
Fixed memory leak inside php_imagettftext_common()
Make ext/gd compile with GD 2.0.17+ (gdFreeFontCache() is not avaliable)
This initial checkin has no changes to any of the libgd code so it can
be used as a basis for diffs. It also will not build currently because
of this. The PHP gd checks need to be incorporated along with a bit of
other config magic. It also shouldn't break the build and will only
take effect if you use --with-gd=php right now.
