Improvements to RoadmapScanner and added missing Track pieces

• added JumpRoadpiece
• added LandingRoadpiece
• RoadmapScanner no longer moves the car (user must order car to move)
• improvements to Roadmap:
  -- add() now includes failure robustness (in case an unknown roadpiece occurs)
  -- new normalize() method makes first Roadpiece the StartRoadpiece, regardless of where scanning began
  -- new deNormalize() restores originally scanned track order
  -- new reverse() method reverses the order of scanned (or normalized) Roadmap (second call to reverse() restores the original)
  -- facility to report length of Roadmap with getLength()
  -- facility to compare two Roadmaps with equals()
  -- facility to print Roadmap on Standard Out as a string with toString()
  -- facility to load and save Roadmaps to/form file