toggle( override ) {

		if( typeof override === 'boolean' ) {
			override ? this.activate() : this.deactivate();
		}
		else {
			this.isActive() ? this.deactivate() : this.activate();
		}

	}
Toggles the slide overview mode on and off.

@param {Boolean} [override] Flag which overrides the
toggle logic and forcibly sets the desired state. True means
overview is open, false means it's closed.