avoid erroring due to name-conflicting files from archives when on case-insensitive FS (https://trac.macports.org/ticket/30373)
avoid erroring due to name-conflicting files from archives when on case-insensitive FS (https://trac.macports.org/ticket/30373)

git-svn-id: 620571fa9b4bd0cbce9a0cf901e91ef896adbf27@81562 d073be05-634f-4543-b044-5fe20cf6d1d6

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