Fixed #13279 -- Made the paths in the Unix install docs more explicit. Thanks...

Fixed #13279 -- Made the paths in the Unix install docs more explicit. Thanks to KathyManwaring for the report and stumbles for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14062 bcc190cf-cafb-0310-a4f2-bffc1f526a37