Changed version number to 3.6.1-SNAPSHOT
fixed uneven spacing of hidden dates
Merge remote-tracking branch 'origin/develop' into develop

Conflicts:
	HISTORY.md
	dist/vis.js
fixed uneven spacing of hidden dates
fixed all problems with hiddenDates EXCEPT moment on firefox
fixed all problems with hiddenDates
fixed subgroups and added sorting
Released version 3.6.1