Versioning can be improved

[Morgul]

While releases are versioned with semantic versioning, development versions (like anything pushed out to the beta site) need to contain more information about what the last thing deployed was.

I propose we use a format like this:

<major>.<minor>.<patch>-beta.<prerelease>+<commit sha>

So, for example, the build right after v3.0.0 would have been v3.1.0-beta.1+3e56bf6. This still follows semantic versioning, but it includes useful information for the beta versions that doesn't need to be displayed for the production versions (though should probably be made available through the UI somehow.)

This will require a change to the deployments, but that's already not working as intended, so some work was going to need to be done there anyway.