Explicitly add libpath to loadpath

This makes version checking against "git" obsolete
Remove Redwood.check_library_version_against
Merge pull request #51 from 5long/manage-load-path-in-bin

Explicitly add libpath to loadpath
Merge branch 'develop' into rmail-to-mail
Merge branch 'rmail-to-mail' into rmail-to-mail-initial