Some Upgrades and Fixes

This upgrades includes: 1. fixed: Depot Truck not visible in-game after upgrading to Beta 1.3. The issue was traced to an incorrect vehicle index number in the saved game data, and has been corrected. 2. fixed: Tractor-Trailer cargo not reloading when continuing game. The issue was related to issue 1 and has been corrected (the Depot Hack was inadvertently using the same index number as the trailer). 3. fixed: bridge abutment protruding from terrain on the Observatory Road. A wall has been added to blend the bridge into the terrain. 4. upgraded: various cameras on vehicles and Train #1 have been added, changed, or improved. Camera #2 on vehicles can now orbit the vehicle to provide better views while picking up and delivering cargo, and turning in confined spaces. The End B camera on Train #1 can be slightly moved to provide a better view of the rear coupler area. New cameras include views forward and reverse. 5. new: train bell added to locomotives.