[fix bug 881831] Redirect mozillians registration to the new profile edit screen.
[fix bug 895352] Date involved with Mozilla.

New model fields in UserProfile:
 - date_mozillian
 - privacy_date_mozillian

Tied new model field with profile_edit.html and profile.html.
[fix bug 895352] Add timezones in user profiles.

- Add timezone and privacy_timezone fields in UserProfile
- Update profile_edit.html
- Update profile.html
Merge pull request #553 from Sancus/giorgosprofilefix

fix userprofile stuff