Add API option to set HELO

Added an option to set a HELO when submitting via API, and added support for that to the aboutmyemail client.

Add support for status callbacks

Added the feature to aboutmyemail to run a local webserver to accept API callbacks.

Rename to amemanage, add DNS checks.

setbranding is renamed to amemanage

dns subcommand added, for basic "is my CNAME set correctly?" dns checks.

Linting and bootstrapping

Added an init command to setbranding create an initial set of templates.

Added a lint command to do basic reasonableness testing of templates, also do the same tests before an upload.

First release.

Kicking the github workflow helpers. Let's see if this one works.