Release 7.6.0 - MyQ V6 API

Major update for V6 API using a Python3 subprocess.

Requirements for version 7.6.0 and later:

macOS 10.15.7 or later (for Python 3)
Install and Run Xcode.app (upgrades Python to 3.8.X)

Confirm Python version:

% /usr/bin/python3 --version
Python 3.8.2

Install Python packages:

sudo /usr/bin/pip3 install aiohttp

sudo /usr/bin/pip3 install bs4

sudo /usr/bin/pip3 install pkce