Abstraction #12
Description
Since the "Minecraft Plugin API" seems to more and more in range, we should consider designing most core stuff independently of Bukkit to be able to support all systems at least with some basic functionality.
The registry/dependency-handling design should allow to build system-dependent checks quickly where needed.
Check design might well split things into components, some of which may be fully abstracted or at least part-generic, but not system-dependent. (part-generic would rely on a service for that generic class, but does not need specific knowledge other than results of queries to the service).
Focus of the splitting question might be how to organize the violation handling if actions can be performed at any stage of checking. In fact this means we have providers that are already checks and might or might not put through data, depending on if/how actions have been triggered.