Add additional robustness to Xcode search.
Add additional robustness to Xcode search.

 - In the event that mdfind fails to find anything, also look for Xcode.app in /Applications and /Developer/Applications
 - If no Xcode.app is found, present a message to the user asking them to install it.

git-svn-id: 620571fa9b4bd0cbce9a0cf901e91ef896adbf27@90071 d073be05-634f-4543-b044-5fe20cf6d1d6

macports/macports-base,danchr/macports-base,danchr/macports-base,neverpanic/macports-base,macports/macports-base,neverpanic/macports-base