Stackmanager

* Fix (hopefully) CodeBuild issue with Docker push

* Include curl in the Docker image
* Tag image with minor/major/latest - e.g. 1.2.4 will also be tagged 1.2, 1 and latest.

Switches Docker image to be Debian based for compatibility with Azure DevOps - otherwise identical to previous 1.2.x versions.

Identical functionally to 1.2.0 (and 1.2.1), but includes Docker image in AWS Public ECR

* Enable Termination Protection **by default** when creating or updating stacks
* If there are no changes when doing a `deploy`, but Termination Protection is not currently enabled, it will add termination protection (whether supplying `--auto-apply` or not)
* Add `TerminationProtection: False` to the config file if you don't want Termination Protection
* Termination Protection will automatically be disabled when you run the `delete` command if set
* Require confirmation for the `delete` command, either by supplying the `-Y/--yes` flag, or the interactive prompt.

* Print stack outputs after executing change set or displaying stack status
* Add `get-output` command to return the value of a single output for use in scripting
* Errors now go to stderr