test-gh-action-versioning

testing gh action with versioning

Process

1. Maintainer sets SOFTWARE_VERSION.
2. New pushes to master branch trigger a build; VERSION is updated, and tagged images are built and pushed to Docker Hub based on VERSION, SOFTWARE_VERSION (as well as latest).

TODO

1. Check if the build version should go back to 0 if the software version changes. For example, if we were at 2.0.0--10 and we changed the SOFTWARE_VERSION to 3.0.0, we would want the new version to be 3.0.0--1, not 3.0.0--11. We could alter this to change the build number to be a datetime instead, which would address this (and allow a user to determine which is a newer image still).