Install gcc 4.8 on osx 10.10
Install gcc-4.9 on yosemite

Includes patch from homebrew/homebrew#31466
Patch gcc 4.8.3 for yosemite support

See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61407 and
http://patchwork.ozlabs.org/patch/360446/
Actually apply the gcc 4.8 patch on yosemite
Use a different patch for gcc48

The patch from bugzilla doesn't apply cleanly to 4.8.3, but a more
recent one from the gcc-patches mailing list does:
https://gcc.gnu.org/ml/gcc-patches/2014-08/msg02427.html
Go back to gcc 4.8 on yosemite for now
Remove gcc49, it didn't work anyway
Use the right gcc version on 10.9 too
Merge pull request #12 from boxen/yosemite

Install gcc48 on Yosemite