Add a benchmark for calling ConnectBlock on a block with many inputs

Requires placing block-107134.tar.gz (containing the block, and a fake CoinsDB
containing its inputs) into the base directory of the repository. This can be
generated using qa/zcash/create_benchmark_archive.py (see the script for usage
details).

To facilitate generation of the fake CoinsDB, an additional field 'valueZat' has
been added to 'getrawtransaction' containing the integer number of zatoshis
instead of a decimal number of ZEC.

Closes #2355.

src/rpcrawtransaction.cpp

@@ -137,6 +137,7 @@ void TxToJSON(const CTransaction& tx, const uint256 hashBlock, UniValue& entry)
         const CTxOut& txout = tx.vout[i];
         UniValue out(UniValue::VOBJ);
         out.push_back(Pair("value", ValueFromAmount(txout.nValue)));
+        out.push_back(Pair("valueZat", txout.nValue));
         out.push_back(Pair("n", (int64_t)i));
         UniValue o(UniValue::VOBJ);
         ScriptPubKeyToJSON(txout.scriptPubKey, o, true);