[1.2.X] Fixed #10078 - Document use of locales in management commands. Thanks...

[1.2.X] Fixed #10078 - Document use of locales in management commands. Thanks gregoire for the suggestion and ramiro for the patch.

Backport of r15141 from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15142 bcc190cf-cafb-0310-a4f2-bffc1f526a37