Merge pull request micropython#1186 from dhalbert/uart-enhancements UART enhancements

Merge pull request micropython#1131 from tannewt/hallowing3 Support Hallowing in 3.x

Merge pull request micropython#1036 from hathach/fix_nrf52840_serial Fix nrf52840 serial mentioned micropython#1021

Merge pull request micropython#1006 from dhalbert/3.x-fix-pull must set pull after setting direction with gpio_set_pin routines

Merge pull request micropython#986 from tannewt/include_rtc_fix include RTC fix for SAMd51 in circuitpython build

Merge pull request micropython#945 from tannewt/nrf52832 Switch to Feather52s full name to avoid confusion with the nrf52840 later

Add trailing dash so that the exact board is matched. 

Merge pull request micropython#866 from tannewt/touchio3 Use merged in FreeTouch

Merge pull request micropython#812 from dhalbert/2.x-filesystem-writa… …bility-on-boot 2.x: Fix regression preventing remount as readwrite in boot.py

Merge pull request micropython#802 from dhalbert/2.x-filesystem-work 2.x: handle bad power on reset better