Remove all support for the CC3200 and CC3200-Launchpad.  This was a port that was started but never completed.  What good is partial CC3200-Launchpad board support with no wireless support?

Squashed commit of the following:

    Remove final references to CC3200 from the repository.
    arch/arm/include/tiva:  Remove all CC3200 support.
    arch/arm/src/tiva:  Remove all CC3200 support.
    configs/cc3200-launchpad:  Remove the board support directory.