submodule lufa, tag/version 140302
switch to lufa 140302

    some function calls/parameters and constants changed

    checkinvalidevents removed, as there is no such target in the
    original makefile anymore

    programming target probably doesn't work anymore, as the endpoint
    must be re-defined

    deleted old lufa dir, new lufa is submodule, see
    b583437183ef61d56213dccaae655728fabc4d71