[CSL-164] Add 'instance ToJSON PublicKey'
[CSL-164] Add 'instance ToJSON PublicKey'

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