Added email verification for users

The verification email is sent if needed when profile is updated (either when the email is changed from the previous time or it was an old account and didn't have the token value)

You can test it here: http://verify.gae-init.appspot.com/profile/

![screen shot 2014-08-14 at 19 46 25](https://cloud.githubusercontent.com/assets/125676/3924464/a9cb5d1e-23dd-11e4-9c63-54d00363f42c.png)
The third person shouldn't click on the link :P

But yes.. I can see what can go wrong.. so maybe we'll have to use the `login_required` after all..