ability to separate compilation parameters for different compilers / create a compilation configuration object

I think we should introduce a compilation configuration object (and deprecate but not remove the old parameters) in the compiler plugin. This can have a base class that is extended by the different compiler types.

I'm not sure if the Maven processing does enough just yet to be able to set a specific field with the right type without setting implementation="" however, and we should also be able to make the object a fullly-fledged component (with expressions and default values, as long as it is in the same source tree).