Upgrade gnome-common to version 3.4.0.1.
Add a dep on `xz`.
Add a patch to help `gnome-autogen.sh` to accept automake-1.12
as being greater than 1.09.
Tested on Lion with clang and llvm from XCode-4.3.3.
ClosesHomebrew/homebrew#13420.
Signed-off-by: Adam Vandenberg <flangy@gmail.com>