Blockly status

@BrettASwift @AmbientOSX This PR has execution tracing for the forward, left, and right blocks: highlighting in the window and display in the lower right corner of the HUD. 

This is to get something in for today, things I will continue:
- Draw blocks in hud from svg references, instead of static images
- While block inclusion

Uses virtual-world-framework/vwf#273
I'd rename the method to `executeBlock` and the event to `blockExecuted` for clarity.