Libraries should use semantic versioning

[rien]

We're noticing more developers are using our library (dolos-lib) and with the new core library coming up (dolos-core) we should adhere to semantic versioning.

Up till now we've used the same version for all our packages, and we've only bumped our major version when Dolos had a drastic UI change. However, we've often made breaking changes to our library which should've been a major version bump. This makes it hard for dependents to integrate our libraries.

I propose we keep our current versioning scheme for our apps (CLI and Web UI), but switch to semantic versioning for the libraries. To signify this change, we can bump dolos-lib and dolos-core in our next release to 3.0.0.

Future releases will always release a new version of our apps (CLI, Web UI or webserver), but the libraries might not change.

[rien]

We have been implementing this lately, so this issue can be closed.