also pass an object to tone() in order to support visual feedback for playing a particular note in a tune.
Added the test.
Merge branch 'master' into bw21

* master:
  Fixed key signature parsing.

Conflicts:
	musical.min.js - recompiled that
Merge branch 'master' of https://github.com/PencilCode/musical.js into bw21

* 'master' of https://github.com/PencilCode/musical.js:
  Round to the closest millisecond.
  Improve timing tests by using sinon fake timers.

Conflicts:
	musical.min.js
fixed the test (passing origin) according to work with commit 2798fc7
Remove trailing spaces.