Pest control

- Fixed error when running a program with an empty loop
- Fixed pickups not coming back when scenario is reset (upon failure and going back through pause menu)
- Fixed subtitle box being on top of the Blockly window
- Fixed Blockly window hiding at the start of a few scenarios
- Fixed objects showing up under the ramp (at [0,0,0]) before they are placed on the grid

@kadst43 @AmbientOSX @ajiraffe