Rework handling various responses and operations

[cincuranet]

I.e. the ProcessOperation and i.e. CryptKeyCallbackResponse handling (especially the Identify part that duplicates the reading and writing of Version15.CryptKeyCallbackResponse).

Maybe this handling should be encapsulated into responses themselves, especially the ones in Identify and Attach phase. Because now there's response creation logic and later handling logic (and sometimes the handling works over integer operations only). Or maybe the other way around and places where handling is done only on integer operations, encapsulate that into objects as well.