nrf/boards/microbit: Add copy of microbit display and image files.

ports/nrf/boards/microbit/modules/AUTHORS

ports/nrf/boards/microbit/modules/LICENSE

ports/nrf/boards/microbit/modules/iters.c

ports/nrf/boards/microbit/modules/iters.h

ports/nrf/boards/microbit/modules/microbitconstimage.cpp

ports/nrf/boards/microbit/modules/microbitconstimagetuples.c

ports/nrf/boards/microbit/modules/microbitdisplay.cpp

ports/nrf/boards/microbit/modules/microbitdisplay.h

ports/nrf/boards/microbit/modules/microbitimage.cpp

ports/nrf/boards/microbit/modules/microbitimage.h

ports/nrf/boards/microbit/modules/modmicrobit.cpp

ports/nrf/boards/microbit/modules/modmicrobit.h