Allow configuration file to be specified via a environment variable

[luto]

Fixes #742

This PR enables the configuration file to be specified in the $SUPERVISOR_CONFIG environment variable. Refer to the issue for further discussion.

[mnaberez]

We can't merge any new features that don't have tests. Please remove the unrelated gitignore changes.

[luto]

1. tests: will do
2. gitignore: gotcha. See Add a couple of common python dirs to .gitignore #919

[mnaberez]

Thanks, I've merged #919.

[luto]

@mnaberez got tests now and they pass in the CI. Please let me know if you need anything else! :)

[mnaberez]

I'll test this locally and if I don't find any issues, I'll merge it for the next feature release.

[luto]

Thank you! :)

[luto]

@mnaberez any news on this? :)

[santiagobasulto]

Hello, I came here searching for this. Any news on when it's planned to be merged/released?

[mjpieters]

I'd have created this very pull request if this wasn't here already. What is the status of this, what is missing (if anything) before this can be merged?

[mnaberez]

What is the status of this, what is missing (if anything) before this can be merged?

I reviewed it again and it looks fine to me. I intend to include it in the next release.

[delgor]

Hi, I'd love to see this feature as well. Did anything change since your last review, what is required for this to be merged?

[luto]

We are still interested as well.