[MCC-140733] Feature/show error

PR adds hypermedia error handling for show 404s.  Also adds a spec to check the properties of a drd, and a little light spec refactoring.

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Finished in 37.03 seconds (files took 0.30943 seconds to load)
16 examples, 0 failures, 1 pending
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Oh I forgot to get rid of this, I'm going to.  Also going to create a card in the melting pot to take this out of the error class template.