[1.3.X] Fixed #17737 -- Stopped the collectstatic management command from...

[1.3.X] Fixed #17737 -- Stopped the collectstatic management command from copying the wrong file in repeated runs. Thanks, pigletto.

Backport from trunk (r17612).

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.3.X@17613 bcc190cf-cafb-0310-a4f2-bffc1f526a37