REV3.1 - Dec 23 2021:
  - Added missing pull-up/pull-dn resistors
  - Improved input power section
  - Improved audio section
  - Improved stability of add-on boards
  - UART signals are routed through audio mux instead of I2C signals
  - Adjusted FFC connector positions on display adapter for proper display fit

REV3 - Oct 1 2021:
  - Touch controller is routed to FE310 instead of BT817
  - Added sound multiplexer between amplifier and phone jack/speakers
  - Added BT817 sound connector
  - Changed amplifier volage to 5.0V from BQ25895 boost converter
  - Added console connector and power/reset/alt boot switches for i.MX8
  - Added schottky barrier rectifier for BQ25895

REV2 - Mar 29 2021:
  - Replaced FT813 with BT817 display/touch controller
    BT817 24bit parallel output is serialized using DS90C185
    i.MX8M LVDS output and BT817 output are multiplexed using TS3DV520E
  - Added 2nd MAX98357A amplifier for stereo sound
  - Added FT230X USB to UART interface. Allows programming both fe310 and esp32 without JTAG programmer
  - Added LSM9DS1 accelerometer/gyroscope/magnetometer sensor