First alternative-firmware for OpenHaystack

This release has been tested on E104-BT5032A (an nRF52832 module) and on a nRF518122 module. The advertising interval is set to 5000 ms. The nRF51 has been updated to not use an external crystal to maximize compatibility. However if your board has a crystal you should set the board to BOARD_ALIEXPRESS NRF_MODEL=nrf51 BOARD=BOARD_ALIEXPRESS make build to improve (even more) battery life.