added option for controlling jamming behavior

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@17447 29f149b2-0c63-11e1-8f5c-a347f6a9acd0
patching expected results after adding option refs #21

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@17448 29f149b2-0c63-11e1-8f5c-a347f6a9acd0