start() {
			if (this.active())
				return false;

			this.tick = 0;

			if (this.queue.length) {
				this.timer = window.setInterval(this.step, 1000);
				this.step();
				document.dispatchEvent(new CustomEvent('poll-start'));
			}

			return true;
		}
(Re)start the polling loop. Dispatches a custom `poll-start` event
to the `document` object upon successful start.

@instance
@memberof LuCI.poll
@returns {boolean}
Returns `true` if polling has been started (or if no functions
where registered) or `false` when the polling loop already runs.