Versioning system

[gsteinLTU]

Ideally, old versions of extensions should be accessible in some way in order to preserve older demos. It makes sense to have a version number included with the extension metadata so we could support automatic upgrades with semantic versioning for projects made in older versions.

@dragazo has a good idea with using a Github Action. Maybe we can make it use a different branch for Pages, have the action check if the version number for one changed and then create a new folder for it (I'd keep the current URLs valid for the newest version). Maybe another generated file of available versions?

[gsteinLTU]

A thought we had today, maybe it could upload the site to S3 instead of adding many copies of every asset for every extension to the repo.