Module-local test framework

[elsirion]

For module level integration tests it would be great to have a framework where only one module is run in a fake consensus server/client. We currently use a whole consensus server with the dummy module and the module to be tested for module-level tests, but that's unnecessary complexity and e.g. doesn't allow simulating specific/rare AlephBFT behavior.

[justinmoon]

dev call: could also be faster