Don't merge in translations twice from deprecated project level tree when it...

Don't merge in translations twice from deprecated project level tree when it is also listed in LOCALE_PATHS. Thanks Claude Paroz. Refs #14924.
Also, removed some old unused variables as reported by pyflakes.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15514 bcc190cf-cafb-0310-a4f2-bffc1f526a37