The audio output is still messed up, but this commit gets everything as
ready as it can get. Fixed up all the testbenches and added state
machines for everything
These were realy headaches but the testbenches are passing. We need to
take a look at the audio_buffer testbench for sure, it is way wrong and
needs reworked to use the interface. Should do a pass through every
module probably.
This module needs way reworked to just be a state machine. I was trying
to get way too tricky with it so I went back to the drawing board and
made a state machine diagram for it. The diagram is included with this
commit. I also moved the current collection of documentation to a doc/
folder, and added a second-long audio rom to test everything out once
the rom_sd is working.
