remove-loops now only tries to remove turn-arounds at the start and end of a route. Loops in between are already handled by the search for a cheaper alternative. refs #335

git-svn-id: http://svn.code.sf.net/p/sumo/code/trunk/sumo@16971 29f149b2-0c63-11e1-8f5c-a347f6a9acd0