moving actions for custom domain in its own controller
use separate service class for custom domains
updated help text for custom domains
increased test coverage for custom domains
About track requests:
Create migration that adds the fields submitter_id, state, and
cfp_active to Tracks
Add validations and the self_organized? method to the Track model
Create a new TracksController outide of the admin namespace
Create the relevant views for index, show, new and edit
Modify the admin views for tracks to include extra info for
self-organized tracks
About track organizers:
Create the role when a self-organized track is created
Define track organizer abilities
Modify the roles views and controller to handle the new role
The route for Roles#edit needs to have higher priority than the nested
routes for track roles, otherwise, the word edit in the url is matched
as a track with short_name edit
