Implement track request acceptance

Allow track submitter to request specific dates
Redirect to Tracks#edit if a track doesn't have a room or start/end date
before accepting it

Don't allow the submitter or the track organizers to edit the request
after it has been accepted or confirmed

Restrict track selection in proposals and move track selection from
Proposals form to events helper

Mark cfp_active of the tracks table as not null and fill in true if nil

app/controllers/tracks_controller.rb

@@ -4,7 +4,7 @@ class TracksController < ApplicationController
   load_and_authorize_resource through: :program, find_by: :short_name
 
   def index
-    @tracks = current_user.tracks.where(program: @program)
+    @tracks = @tracks.where(submitter: current_user)
   end
 
   def show; end
@@ -38,9 +38,33 @@ class TracksController < ApplicationController
     end
   end
 
+  def restart
+    update_state(:restart, "Track #{@track.name} re-submitted.")
+  end
+
+  def confirm
+    update_state(:confirm, "Track #{@track.name} confirmed.")
+  end
+
+  def withdraw
+    update_state(:withdraw, "Track #{@track.name} withdrawn.")
+  end
+
   private
 
   def track_params
-    params.require(:track).permit(:name, :description, :color, :short_name)
+    params.require(:track).permit(:name, :description, :color, :short_name, :start_date, :end_date)
+  end
+
+  def update_state(transition, notice)
+    errors = @track.update_state(transition)
+
+    if errors.blank?
+      flash[:notice] = notice
+    else
+      flash[:error] = errors
+    end
+
+    redirect_back_or_to(conference_program_tracks_path(conference_id: @conference.short_title))
   end
 end