Update js/jquery.fn.gantt.js

Fixes deadlock (and chrome/IE/firefox) crash, because of applying floor to current date (variable doesn't increment).
Update js/jquery.fn.gantt.js
Merge pull request #63 from kripper/patch-1

Update js/jquery.fn.gantt.js
Merge remote-tracking branch 'upstream/master'

Conflicts:
	js/jquery.fn.gantt.js