Thorough Cpu Planning.

This project benefited greatly due to the three weeks spent working out on paper exactly what the different instructions need to do and how those instructions fit into the larger picture. With each instruction layout mapped out and then rewritten up with all the other instructions, errors and discrepancies were discovered earlier rather than later, after the datapath was put together. In general, it is much easier to fix a bug when it is on paper than discovering the bug inside the signal debugger, hidden behind a swarm of other signals.