WINDUP-253  Refactor WindupProcessor/Impl

Refactor WindupProcessor/Impl to simplify the API, move inner classes out and offload part of the code like prettyPrintRule() out of this important class.
Specific use case pls :) Most likely this will only be used in test, eclipse, forge service. How about adding it as a list when it's needed? We can add it, but personally I would keep the API simple.