initialize mopro with arkzkey and wasm

[vivianjeng]

Implementation for https://github.com/oskarth/mopro/issues/65

• update MoproCircom to initialize with arkzkey and wasm
• download arkzkey and wasm in KeccakSetupViewController

• result KeccakSetupViewController (this PR)

  Download wasm took: 0.6701240539550781s
  Download ark key took: 1.6424980163574219s
  
  Initializing arkzkey and wasm took 8.671825051307678s
  
  Proof generation took 1.5237200260162354 seconds.
  
  Proof verification succeeded.

  KeccakZkeyViewController (generateProof2)

  Initializing arkzkey took 8.844295024871826 seconds.
  
  Proof generation took 1.4890559911727905 seconds.

• result in iPhone device (iPhone 12 mini) (This PR)

  (generateProof2)