Updating GPS documentation with details on how to enable GPS.

docs/Gps.md

@@ -2,6 +2,18 @@
 
 Two GPS protocols are supported. NMEA text and UBLOX Binary.
 
+## Configuration
+
+Enable the GPS from the CLI as follows:
+
+1) first enable the `feature GPS`
+2) set the `gps_provider`
+3) if required, set your GPS baud rate using `gps_baudrate`
+4) connect your GPS to a serial port that supports GPS and set an approprate `serial_port_x_scenario` to `2`. where `x` is a serial port number.
+5) `save`.
+
+For the last step check the Board documentation for pins and port numbers and check the Serial documentation for details on serial port scenarios where you will also find some example configurations. 
+
 ## GPS Provider
 
 Set the `gps_provider` appropriately.