Copy the Physics example, will do a round of improvements on it.
Draw agents on canvas rather than from a sprite, lets me adjust size and have the gfx update
Reduce agent size, will put in some separation behaviour to make them stay more apart.
Reduce garbage generation when updating the dijkstra field and flow field
Notes on SC2 pathing from the GDC video
Debug draw the forces
Twiddle with flocking stuff. may or may not be better, I think it is...
Initial checkin of 2 groups crashing in to each other. No other obstacles, using seek behaviour.