[CSL-865] Add tests to recently added cryptographic primitives
[CSL-865] Add tests to recently added cryptographic primitives

Because the 'Pos.Crypto' import in the 'Test.Pos.CryptoSpec' module
was getting too large, a qualified import of that module is now
used.

input-output-hk/pos-haskell-prototype,input-output-hk/cardano-sl,input-output-hk/cardano-sl,input-output-hk/cardano-sl,input-output-hk/pos-haskell-prototype,input-output-hk/cardano-sl,input-output-hk/pos-haskell-prototype