Random graph generation

Added button and algorithm to generate a graph.
Added control and functionality to show open and closed list from A* search.
Added UI radio buttons for either showing number, color, both, or none for MU visualization.
Changed canvasSize to 600
Extracted some mouseup handlers to functions, so that I can removeEventListeners and addEventListener as one pleases, I needed to do this to enable continuous drawing on the new grid. This required moving some stuff outside function definitions like exporting isDrawing boolean outside the function defintion.

The radius thing is experimental and mostly not working? Can you ignore that?

With the current state, this branch works and generates random graphs with water and disturbances.

Fixes #67

JonasStjerne / resilient-pathfinding