C: Ignore Some Common File Extensions for Binaries on Linux

 I use this system in a few of the projects I've contributed to, to
ignore architecture-specific linux binaries.
Merge branch 'master' of git://github.com/github/gitignore into add-common-linux-compile-file-extensions

Conflicts:
	C.gitignore

Updates done.
Merge branch 'master' into add-common-linux-compile-file-extensions

I messed this up partially.
Merge branch 'master' into add-common-linux-compile-file-extensions

Upstream merges
Merge branch 'master' into add-common-linux-compile-file-extensions

More upstream merges
Merge branch 'master' into add-common-linux-compile-file-extensions

More updates
Merge branch 'master' into add-common-linux-compile-file-extensions
Merge pull request #875 from four04/add-common-linux-compile-file-extensions

C: Ignore Some Common File Extensions for Binaries on Linux