UserInterfaceState.xcuserstate 삭제하기

git rm --cached ProjectFolder.xcodeproj/project.xcworkspace/xcuserdata/myUserName.xcuserdatad/UserInterfaceState.xcuserstate
git commit -m "Removed file that shouldn't be tracked"

http://stackoverflow.com/questions/6564257/cant-ignore-userinterfacestate-xcuserstate