[Feature Request] Disable analysis per project

### Problem
I have many assemblies in my workspace. That causes the IDE to slow down *really badly*.

I know that it's possible to target a single project rather than the whole workspace, but that's not convenient - I need to have multiple projects analyzed, and multiple projects ignored.

### Solution
It would be nice to be able to disable analysis for *certain projects*, using an assembly attribute, or a config file option, etc.

I would then exclude projects that are not often touched - e.g. "common" projects, test projects.