[WIP] Template fixes

- `send` method change to public in email service
- fixed users API response status code to 403 when wrong password while logging in
- removed smarty function: user_key (moved to tw extra plugin)
- registration confirmation process fix (terms of use and user avatar)
- [CS-4990] $gimme->current_list->count gives wrong count
- [CS-4948] - add user image to api

Info how to generate user image, read user api doc:
`http://example.com/documentation/rest-api#get--content-api-users-{id}.{_format}`

- containers declaration change in UserCommentsList to list user comments using extra plugin route (`/user/profile/David+Bauer`)