Squashed commit of the following:

    apps/graphics/ft80x:  Replace polling logic with gentler signal logic when waitinf for the CMD FIFO to become empty.
    apps/examples/ft80x:  Add first co-processor example.
    apps/graphics:  Extend library to manage display lists either in display memory (RAM DL) or provided directly to th co-processor FIFO (RAM CMD).
    apps/examples/ft80x:  Some minor clean-up.  Trivial changes for coprocessor support.