Docker Environment Variables for defining thresholds and notifications

[armond-avanes]

Is your feature request related to a problem? Please describe.
Yes. I have my entire homelab setup automated by Ansible (all docker containers); but one of the things that I need to do manually after the setup, is to launch Speedtest-Tracker web interface and to manually define my thresholds and notifications which is a pain.

Describe the solution you'd like
It would be great if the thresholds and notifications could be defined as docker environment variables (at least as initial values which can be later changed in the web UI).