FIXED GraviTrax Tipper

Remix of https://www.thingiverse.com/thing:5378.658Fixed 5 problems with the original design:1. One fulcrum holder on the base had a hollow hole underneath.2. Non-manifold areas in the model.3. Raised fulcrum so that the tip tube is at entrance (more tipping action).4. Curved the fulcrum mounting holes so the tipping part will snap in and stay in place, and not be lost as a separate part in the toy box.5. Moved the fulcrum back so that the tip tube would actually tip when the last marble rolls in