This is a quick commit. I gave admins the ability to ban or unban users

straight from the moderation.users_detail page. I also changed the
UserBan.expiration_date type from DateTime into Date. I also began work on the
Terms of Service, pulled from another website (which will be cited clearly
before I'm done). I added new tests as well for the ban/unbanning. Lastly,
I added a few `user_not_banned` decorators to relevant views, so banned users
cannot access any pages.

mediagoblin/user_pages/views.py

@@ -367,6 +367,7 @@ def collection_list(request, url_user=None):
 @get_user_collection_item
 @require_active_login
 @user_may_alter_collection
+@user_not_banned
 def collection_item_confirm_remove(request, collection_item):
 
     form = user_forms.ConfirmCollectionItemRemoveForm(request.form)