* Add uniqueness validation to broadcast titles in broadcast.rb
* WIP: properly test title uniqueness in broadcast_spec.rb
* Add unique index for title and type_of on Broadcasts
* Adds a unique index to the Broadcasts table
* Adds broadcast.rb to .rubocop_todo.yml
* Resolve merge conflicts
* Add spec around duplicate broadcasts in broadcasts_spec.rb
* Adjust broadcast to be inactive in broadcasts_spec.rb
* Differentiate between welcome + announcement broadcasts
* Allow admins to filter between these two types in the `/internal/broadcasts` UI.
* Ensure that the index endpoint fetches the correct Broadcast models.
* Only allow one Announcement broadcast to be created at a time
* Also add some `announcement` and `welcome` scopes on the `Broadcast` class.
* Add flash[:success] messages in BroadcastsController.
* Add some tests for Announcement broadcast validations
* Remove unused active_announcement_params method
* Order Broadcasts by title, optimization improvements
* Fix missing closing tags in broadcast specs
