message: Add clearmempool rpc call.
diff: @@ -528,6 +528,22 @@ UniValue mempoolToJSON(bool fVerbose)
  }
  }
  +static UniValue clearmempool(const JSONRPCRequest& request)
  +{
  + if (request.fHelp || request.params.size() > 1)
  + throw std::runtime_error(
  + "clearmempool\n"
  + "\nRemoves all transactions from the mempool\n"
  + "\nExamples:\n"
  + + HelpExampleCli("clearmempool", "")
  + + HelpExampleRpc("clearmempool", "")
  + );
  +
  + LOCK(mempool.cs);
  + mempool.clear();
  + return NullUniValue;
  +}
  +
  static UniValue getrawmempool(const JSONRPCRequest& request)
  {
  if (request.fHelp || request.params.size() > 1)
  @@ -2315,6 +2331,7 @@ UniValue findserial(const JSONRPCRequest& request)
  static const CRPCCommand commands[] =
  { // category name actor (function) argNames
  // --------------------- ------------------------ ----------------------- ----------
  + { "blockchain", "clearmempool", &clearmempool, {} },
  { "blockchain", "findserial", &findserial, {"serial"} },
  { "blockchain", "getblockchaininfo", &getblockchaininfo, {} },
  { "blockchain", "getchaintxstats", &getchaintxstats, {"nblocks", "blockhash"} },
  