Drift 4000 update 1.1

Added a checkpoint when you dock to the derelict. Clicking "CONTINUE" from the main menu will load the game at the point when you last docked to a derelict so you can try different loadouts on the same wave. Quick loading will load the game at the last save (i.e. when you last undocked from a derelict) so you don't have to rebuild your ship every time you die. - Fuel tanks now automatically jettison when they completely run out of fuel (you will still need to manually jettison them to prevent engine sputtering when they get low). - Fixed rare crash when selecting chassis.