NRF51 Port#92

Draft

bezmi wants to merge 2 commits intoahtn:masterfrom

bezmi:32u4_nrf51_esb

Commits on Apr 4, 2019

added some files to start developing support for mitosis receiver (32u4 talking to nrf51 via uart) and the nrf51 in general (for keyboard transmitters)
bezmi
committed

Commits on Apr 5, 2019

removed todo.txt, added README.md
bezmi
committed