Fixed #10175 -- Changed the Serbian translation to use Cyrillic for 1.1.

Thanks Janos Guljas for the patch and the entire sr team on django-i18n
for discussion around this issue.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10468 bcc190cf-cafb-0310-a4f2-bffc1f526a37