This was a simple commit. I changed all references to Groups into Privileges so

This was a simple commit. I changed all references to Groups into Privileges so
as to not conflict with the new federated groups which are also being written.
I also fixed up some of the code in the user_in_group/user_has_privilege decor-
ator. Users are now assigned the default privileges when they sign up, and ass-
iged active once they are activated. I updated the gmg command makeadmin to use
my groups as well. Lastly, I added the decorator to various views, requiring th-
at users belong to appropriate groups to access pages.

--\ mediagoblin/auth/tools.py
--| Added code to assign new users to default privileges

--\ mediagoblin/auth/views.py
--| Added code to assign users to u'active' privilege once the email
  | verification is complete

--\ mediagoblin/db/migrations.py
--| Renamed Group class to Privilege class

--\ mediagoblin/db/models.py
--| Renamed Group class to Privilege class

--\ mediagoblin/decorators.py
--| Renamed function based on the Group->Privilege change
--| Rewrote the function to be, ya know, functional

--\ mediagoblin/gmg_commands/users.py
--| Changed the 'makeadmin' command to add the target user to the admin
  | privilege group as well as affecting 'is_admin' column

--\ mediagoblin/submit/views.py
--| Added the requirement that a user has the 'uploader' privilege in order
  | to submit new media.

--\ mediagoblin/user_pages/views.py
--| Added the requirement that a user has the 'commenter' privilege in order
  | to make a comment.
--| Added the requirement that a user has the 'reporter' privilege in order
  | to submit new reports.
--| Got rid of some vestigial code in the file_a_report function.