Ignore "build" directory created by Xcode

Signed-off-by: Greg Hurrell <greg@causes.com>
Update WO_EXPORT_CLASS macro for 64-bit Mountain Lion

The old `.no_dead_strip` doesn't work when targeting x86_64 on Mountain
Lion, but the good news is that a simpler trick that doesn't require
inline assembly now does work.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Silence some Clang warnings about format string markers

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Silence another Clang warning about incompatible types

This looks like it was a bug; there don't appear to be any reasonable
circumstances under which we'd want to return an NSMutableArray here
(there is no inheritance relationship or common interface).

Signed-off-by: Wincent Colaiuta <win@wincent.com>