Start Using Semantic Versioning for Project Releases

[cnatale]

Right now, staying up to date with Stable Diffusion Webui releases means pulling directly from the master branch. This results in a high velocity of great new functionality, but also an increased chance of pulling in unexpected breaking changes.

I propose adopting a semantic versioning approach to releases in tandem with the current direct merges to master branch. The idea is that by using Github's tagged releases functionality, merges with expected breaking changes are marked as major version updates. Changes with new functionality are marked as minor version updates. Changes that patch existing functionality are considered patch version updates.

Ex:
-Breaking changes are introduced. update from v 1.0.0 to v 2.0.0
-A new feature is added that isn't anticipated to break any changes. update from v 2.0.0 to v 2.1.0
-A bug in an existing feature is patched. update from v 2.1.0 to v 2.1.1

I'm happy to help set up this process. More info on semantic versioning (semver) is available here: https://semver.org/