message: mintmanyzerocoin fixes:
  update help message
  display help message on entering command
  fail should available balance be greater than mint amount requested
diff: @@ -59,6 +59,22 @@ void EnsureWalletIsUnlocked()
  throw JSONRPCError(RPC_WALLET_UNLOCK_NEEDED, "Error: Please enter the wallet passphrase with walletpassphrase first.");
  }
  +bool MintBalanceAvailable(const UniValue& data){
  + vector<string> keys = data.getKeys();
  + CAmount total = 0;
  + int denomination;
  + int64_t amount;
  + BOOST_FOREACH(const string& denominationStr, keys){
  + denomination = stoi(denominationStr.c_str());
  + amount = data[denominationStr].get_int();
  +
  + total += denomination * amount * COIN;
  + }
  +
  + return (total <= pwalletMain->GetBalance());
  +
  +}
  +
  void WalletTxToJSON(const CWalletTx& wtx, UniValue& entry)
  {
  int confirms = wtx.GetDepthInMainChain();
  @@ -2750,7 +2766,7 @@ UniValue mintzerocoin(const UniValue& params, bool fHelp)
  UniValue mintmanyzerocoin(const UniValue& params, bool fHelp)
  {
  - if (fHelp || params.size() > 1)
  + if (fHelp || params.size() != 1)
  throw runtime_error(
  "mintmanyzerocoin {<denomination>(1,10,25,50,100):\"amount\"...}\n"
  + HelpRequiringPassphrase()
  @@ -2762,9 +2778,13 @@ UniValue mintmanyzerocoin(const UniValue& params, bool fHelp)
  " ,...\n"
  " }\n"
  "\nExamples:\n"
  - + HelpExampleCli("mintmanyzerocoin", "\"\" \"{\\\"25\\\":10,\\\"10\\\":5}\"")
  + + HelpExampleCli("mintmanyzerocoin", "\"{\\\"25\\\":10,\\\"10\\\":5}\"")
  );
  + if(!MintBalanceAvailable(params[0].get_obj())){
  + throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, "Insufficient funds");
  + }
  +
  int64_t denominationInt = 0;
  libzerocoin::CoinDenomination denomination;
  // Always use modulus v2
  