Fracking: Don't stop the model while drilling

We probably want methane extraction to continue on already drilled
wells.
Fracking: Fix gas agent behavior for edge cases

Beyond the edge of the pipe, behind the bend, etc.
Fracking: Don't flood other wells' open patches
Fracking: Only start up one reporting timer
Fracking: Speed up patch drawing by only redrawing the affected patches
Fracking: Init wells array in setup
Fracking: Speed up the fill-and-frack color cycling