message: [doc]: update txfactory usage
diff: @@ -20,7 +20,10 @@ FLAGS:
  -V, --version Prints version information
  OPTIONS:
  - -d, --faucet-address <faucet-address> [default: 0xa550c18]
  + -a, --account-address <account-address> account used to send txn, use default account if not specified
  + -p, --account-password <account-password> [default: ]
  -i, --interval <interval> interval(in ms) of txn gen [default: 3000]
  - -p, --ipc-path <ipc-path>
  -```
  \ No newline at end of file
  + --ipc-path <ipc-path>
  + -r, --receiver-address <receiver-address> address to receive balance, default faucet address
  + -k, --receiver-public-key <receiver-public-key>
  + public key(hex encoded) of address to receive balance, default to none```
  \ No newline at end of file
  