flockblock -- USe a Raspberry Pi to create a mobile flock blocker based on geofencing

This code, and documentation is stored on Git. Please find it here: flockblock.py This is my first attempt at coding in Python. So be kind.

Prerequisites

• A Raspberry Pi. Has been tested with models B+ (aka Pi 1), 2, and 3. Should work also with the Raspbery Pi Zero and the Pi 4. Although the Pi 4 is overkill.
• A GPS receiver. Has been tested with Adafruit "Ultimate GPS" serial receiver, u-blox 7 chipset USB receiver, and u-blox 8 chipset USB receiver. Should work with any GPS receiver that can be polled by gpsd.
• Some hardware. Standard configuration uses a relay (opto-isolated) module, two switches, and three LEDs with current-limiting resistors. Although the LEDs are optional, and one of the switches is optional.