Allow an ENV var for APPPACK_TOML to specify the path to the toml file. See Issue #10

[issackelly]

Draft, not yet tested. Pushing to see what parts get built/run/tested automatically on branches

[ipmb]

This looks correct to me. What do you think about factoring this out into a small function?

	filename := "apppack.toml"
	if envFile := os.Getenv("APPPACK_TOML"); envFile != "" {
		filename = envFile
	}

That would be something that we (or your favorite LLM) could add a simple test for. If the tests pass, we can deploy to a canary environment. I can help with that next week.

[issackelly]

This looks correct to me. What do you think about factoring this out into a small function?

	filename := "apppack.toml"
	if envFile := os.Getenv("APPPACK_TOML"); envFile != "" {
		filename = envFile
	}

That would be something that we (or your favorite LLM) could add a simple test for. If the tests pass, we can deploy to a canary environment. I can help with that next week.

Great. What about docs or changelogs for the new behavior?

[ipmb]

https://github.com/apppackio/apppack-codebuild-image/blob/main/CHANGELOG.md

https://github.com/apppackio/apppack-docs/blob/main/src/how-to/apps/apppack_toml.md

[issackelly]

This MR updated and also:
apppackio/apppack-docs#12

[ipmb]

There's a list of headers here at https://keepachangelog.com/en/1.1.0/#how

I would use Added

[ipmb]

why is app.json substituted here?

[issackelly]

These commits should be squashed before merging.