Make task colored with resource colors

[GoogleCodeExporter]

Allow to assign colors to resources and propagate resource color to tasks it is 
assigned to. If multiple resources are assigned then choose either coordinator 
color or color of the "first" resource (or one which is loaded more)

See discussion on the forum:
http://forum.ganttproject.biz/view/20130220222422_3ko05kjjf27g6b8hfkpcofum4

Original issue reported on code.google.com by dbarashev on 1 Mar 2013 at 11:52