Don't go out of our way to validate all dependencies at install time. Also fix an mport reference leak.
Don't go out of our way to validate all dependencies at install time. Also fix an mport reference leak.

git-svn-id: 620571fa9b4bd0cbce9a0cf901e91ef896adbf27@52160 d073be05-634f-4543-b044-5fe20cf6d1d6

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