fixes #155
Remove manual transactions when deleting tags.

Handling the transactions manually creates the possiblity
of unclosed transactions as reported here:
http://askbot.org/en/question/11230/errors-while-trying-to-rename-or-delete-unused-tags/

However, there's no need to do this manual handling; the simplest
solution is to just remove the decorator.

Also added tests.
Append help msg + noinput option to add_admin management command
Oauth2: Facebook: Fix email not found
Fix errors when running migrations against MySQL 5.1.72

Fixes the following type of error:
Error in migration: askbot:0055_auto__chg_field_question_thread
ValueError: The database backend does not accept 0 as a value for AutoField.
Allow Django 1.5.x, not just 1.5 itself

setup.py says that "Django 1.3.1 - 1.5.1" are supported but REQUIREMENTS in __init__.py only allows up to 1.5.
Added support for directly posting as anonymous with recaptcha
make avatar URL configurable
implemented optional display of email addresses to moderators
update of theme for the latest version
minor change contributor info box
Fix database connection issues in prefork mode.

When running in prefork mode, open DB connection got shared between the
child process as DB was accessed very early in the init process. One
child would then close the connection and cause others to fail. To fix
this, connection.close() was added to the end of startup procedures.
Close cache after startup procedures

Same as with DB connection, the cache connection gets shared between child
processes in prefork mode if it isn't closed after startup procedures
Update Thread.deleted when question is restored
Add CSRF protection to comment_to_answer view
Check that user can convert comments or answers
Require loggedin user on answer/comment convert
Monkey patch django.utils.html.escape

Lazy strings get double escaped with django 1.5
https://code.djangoproject.com/ticket/20221
Fix 500 template processing error
fixed a minor issue with displaying user group for anonymous questions on the main page