Reverting change to ignore build subdirectories

Reverted a change that was causing build directories at the root folder to show up in git.  If you need to ignore subdirectories the leading slash needs to be omitted.
Merge branch 'master' into patch-1

Conflicts:
	Objective-C.gitignore
Merge pull request #636 from msgerbush/patch-1

Reverting change to ignore build subdirectories