Add route helper for state machine routes

[itschn]

Example:

      resources :workflows, only: [:show, :index] do
        member do
          Workflow.state_machine.events.map(&:name).each do |event_name|
            patch event_name
          end
        end
      end

should look like:

      resources :workflows, only: [:show, :index] do
        member do
           statemachine_member_actions only: [], except: []
        end
      end

[declarus]

also integrate state scopable concern