Hobbies

This adds "hobbies" functionality to the user profile. This is an extra set of information attached to a user profile which lists their general interests and hobbies. There is an initial list of suggested "official" hobbies, and users can also add their own. This information is entirely voluntary, so completion is not enforced anywhere. There are 2 main parts to this:
  1. A new section in the settings page for "Hobbies"
  2. A hobbies form which is displayed as part of the registration process for new users. This is displayed as the final step before joining a tribe for a new user. It is mandatory to submit the form to proceed, but the form can be empty.