Fixed #16680 -- Used single quotes for the TEMPLATE_DIRS examples in part 2 of...

Fixed #16680 -- Used single quotes for the TEMPLATE_DIRS examples in part 2 of the tutorial to be consistent with the settings.py file generated by the startproject command. Thanks, Michael Tomkins.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16660 bcc190cf-cafb-0310-a4f2-bffc1f526a37