rev-upgrade: Debug-print return value of rebuild procedure
rev-upgrade: Debug-print return value of rebuild procedure

Some rebuilds fail, but rev-upgrade doesn't stop. This is to debug this issue.

git-svn-id: 620571fa9b4bd0cbce9a0cf901e91ef896adbf27@89660 d073be05-634f-4543-b044-5fe20cf6d1d6

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