Remove ConfigurableAggregateTranslator?

[codeliner]

Coming up prooph/event-store v7 no longer contains Aggregate related classes. They are all moved to prooph/event-sourcing. Now we have two AggregateTranslator implementations in one package.
Originally the ConfigurableAggregateTranslator was meant to be a default implementation if one don't want to use prooph/event-sourcing.
With the new structure the ConfigurableAggregateTranslator is no longer needed. prooph/event-sourcing uses the decorator pattern and has its own AggregateTranslator in place.

W could create a gist of the ConfigurableAggregateTranslator instead and link it in the docs if one don't like the decorator approach.

[prolic]

👍 for removing

mentioning it in the docs that this has been removed comletely is necessary. (see my docs-pr #41).

creating a gist is optional I think. You can always implement the translator-interface yourself.