refactoring refs #12

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@15416 29f149b2-0c63-11e1-8f5c-a347f6a9acd0
fixing [15416]. for some reason the test did not fail

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@15417 29f149b2-0c63-11e1-8f5c-a347f6a9acd0
now writing colors as bytes

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@15418 29f149b2-0c63-11e1-8f5c-a347f6a9acd0