Rails 4 introduced "automagically" modified cache keys, that included a digest in the key on any cache entry related to views. This is not what we want at all, fixed here with the `skip_digest: true` option.
Mocking these objects is working differently in Rails 4, and utilising `#and_call_original` helped to ensure different parts of the codebase were receiving the correct response objects (AR relations, etc).
Here the displayed properties that we're testing also rely on shops data (including the list of supplied properties), which is now cached for 15 seconds. We clear that cache entry so we can cleanly test only the caching of the properties AMS array.
