Observable Group Changes + Dropping .Net Framework Builds

Summary

The high level information here is that we have dropped explicit releases for .Net Framework 4.6 and instead are now just focusing on building netstandard2.0, in the future we would like to move to net7 but until a lot more frameworks have migrated over to it we are just going to stick with netstandard.

We have also changed the way ObservableGroup objects work by separating out the group matching mechanism to a new interface known as an IObservableGroupTracker which will monitor the groups/entities and then relay onto the ObservableGroup when there is a change.

This diagram shows the new process, which historically all used to take place within the ObservableGroup so this makes the object simpler and allows other parts of the system to track group changes.

Other Changes

There are some breaking changes around namespaces for events changing as well as a new wrapper around component interactions on the type called IComponentAccessor, which reduce the amount of type lookups if you are doing a lot of interactions with component types.