+Added track speed limit info parsing in parse_switch_prefabs.py
*Renamed parse-prefabs.py to parse_switch_prefabs.py
*parse_switch_prefabs.py will no longer provide track slope and banking information unless specified otherwise with the --extended-track-shape flag
*Modified parse_prefabs.py to use argparse
-Removed shebang from parse_prefabs.py script (caused problems on some python installations)
