constructor( Reveal ) {

		this.Reveal = Reveal;

		this.onNavigateLeftClicked = this.onNavigateLeftClicked.bind( this );
		this.onNavigateRightClicked = this.onNavigateRightClicked.bind( this );
		this.onNavigateUpClicked = this.onNavigateUpClicked.bind( this );
		this.onNavigateDownClicked = this.onNavigateDownClicked.bind( this );
		this.onNavigatePrevClicked = this.onNavigatePrevClicked.bind( this );
		this.onNavigateNextClicked = this.onNavigateNextClicked.bind( this );
		this.onEnterFullscreen = this.onEnterFullscreen.bind( this );

	}
Manages our presentation controls. This includes both
the built-in control arrows as well as event monitoring
of any elements within the presentation with either of the
following helper classes:
- .navigate-up
- .navigate-right
- .navigate-down
- .navigate-left
- .navigate-next
- .navigate-prev
- .enter-fullscreen