Add section about audio controls in README

[yvesgurcan]

Explampify with code how to use pause, resume, and stop in the "Getting started" section of the README and also in the documentation thanks to JSDoc.

web-midi-player/src/MidiPlayer.js

Lines 377 to 384 in 51d8af0

	/**
	* Pauses playback of MIDI input.
	* @param {undefined}
	* @return {boolean} Whether playback was successfully paused or not.
	* @example
	* midiPlayer.pause();
	*/
	pause() {

web-midi-player/src/MidiPlayer.js

Lines 403 to 410 in 51d8af0

	/**
	* Resumes playback of MIDI input.
	* @param {undefined}
	* @return {boolean} Whether playback was successfully ressumed or not.
	* @example
	* midiPlayer.resume();
	*/
	resume() {

web-midi-player/src/MidiPlayer.js

Lines 431 to 437 in 51d8af0

	* Stops playback of MIDI input.
	* @param {undefined}
	* @return {boolean} Whether playback was successfully stopped or not.
	* @example
	* midiPlayer.stop();
	*/
	stop() {