allowing multiple outputs and fixing visualization backend, refs #21

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@16674 29f149b2-0c63-11e1-8f5c-a347f6a9acd0
testing svg output for easier text comparison, refs #21, #1179

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@16675 29f149b2-0c63-11e1-8f5c-a347f6a9acd0