pedersen_hash: prints hashes, adds comments

zcash_proofs/src/circuit/pedersen_hash.rs

@@ -26,6 +26,7 @@ where
     assert_eq!(personalization.len(), 6);
 
     let mut edwards_result = None;
+    //REVIEW: bit cloning
     let mut bits = personalization.iter().chain(bits.iter()).peekable();
     let mut segment_generators = params.pedersen_circuit_generators().iter();
     let boolean_false = Boolean::constant(false);