support for yosemite

add support for latest version of xcode with yosemite

also during my install I saw the error:
xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

which was fixed with:
sudo xcode-select -switch /Applications/Xcode6-Beta4.app/Contents/Developer
sudo xcodebuild --license