added lane coloring by priority fix #1412

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@16927 29f149b2-0c63-11e1-8f5c-a347f6a9acd0
addendum to [16927]

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@16928 29f149b2-0c63-11e1-8f5c-a347f6a9acd0