Reinforce the claim of key ownership on the processors

[tbruyelle]

The goal of this change is to mitigate bugs like the one we have for Iris EmerisHQ/demeris-backend#794, where a trace isn't handled by the correct processor.

The entry point for a processor is the OwnKey method, when it returns true, the trace is passed to Process, meaning the processor will handle it. For most processors, OwnKey just checks if the key starts with a specific prefix, but this is actually too weak because a lot of different modules shares the same prefix. To avoid mistakes, this change adds more constraints like checking if the content of the key matches what is expected for this module.

Since the content of the key for a module can change between sdk version, the code responsible for checking its content has been delegated in datamarshaler/keys_vXX files, and OwnKey just calls it. This change has only been applied to

• bank processor because it's the one responsible of Tracelistener bug: invalid UTF-8 sequence demeris-backend#794
• cw20 processors because they were already checking the key content, but not in the same way.

In the future, if other bugs like that appear, we'll need to port the related processors to this pattern.

Also, I could have done more refac, but I preferred to keep the change simple and review-able in a reasonable time.