GUIHandler: sort chunks before drawing to the window
Main: document intermediate values in preparation for chunking
Bugfix: requested number of chunks may not end up being actual number of chunks
Bugfix: when updating GUI, sort data in the right place to re-order chunks
Update TODO
NodeMain: send response before printing information
Read shutdown values from job response channels
Greatly improve time and space efficiency of GUI by only allocating one image buffer
networkRenderThread: just use forkIO; forkOS does not seem to behave differently
Main: precompute sample data on the master node, send it in the scene setting request, and re-use it for chunk rendering