Invalidate @xcode_version only when we set app.xcode_version, and only call unscape_path once
Invalidate @xcode_version only when we set app.xcode_version, and only call unscape_path once

hboon/RubyMotion,katsuyoshi/RubyMotion,hboon/RubyMotion,katsuyoshi/RubyMotion,hboon/RubyMotion,HipByte/RubyMotion,katsuyoshi/RubyMotion,HipByte/RubyMotion,HipByte/RubyMotion,katsuyoshi/RubyMotion