Store domain in stubs

[shluboto]

Current:

interface.call_count[:update]
interface.calls[:update]

New:

interface.ranking.call_count[:update]
interface.ranking.calls[:update]

interface.profiles.call_count[:update]
interface.profiles.calls[:update]

One MIGHT call use cases from different domains with the same name.

[splattael]

@Shlub Overall, I like the idea.

This change would be a breaking change which would require us to bump the major version.
I am not against it but we should be aware of the breaking change and the version bump.

While bumping a major version we could also improve the interface of interface over all?

For example, I do not like how stubbing results is done via:

result = interface.fake_domain :fake_use_case, :stub_result => { ... }

We should find a nicer way of stubbing things.