Reg 3213 improve robustness of exception handling standalone.py

[monicaihli]

Extensive refactor addresses several issues.:
(1) Script in existing form permitted failed key generation to proceed with installation. Any failure to substitute default keys with dynamically generated keys should not be allowed to progress, in order to prevent security risk of duplicate keys.
(2) Clarified the nature of errors being reported in messages to user during installation. Ensured all possible points of failure are now explicitly addressed.
(3) Refactored out redundant code to improve maintainability.
(4) Added logic to use either v1 or v2 docker compose, depending on what is installed on local system.

[BelardoA]

I tried running this on a fresh ubuntu docker container and fresh ubuntu vm and here are my takeaways:

• It assumes I have pip3 installed, it should follow the logic to see if pip3 is installed and if not it installs it (if not the documentation should have prerequisites before running standalone.py
• It errors when trying to install docker: Unknown error installing dependency: No module named 'docker'. and exits
• The script doesn't work on python 3.8, so possibly add a python version check before proceeding as well like the pip check