trying to fix performance tests, refs #21

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@17511 29f149b2-0c63-11e1-8f5c-a347f6a9acd0
updating documentation to reflect the current behavior refs #2

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@17512 29f149b2-0c63-11e1-8f5c-a347f6a9acd0