btcctl: add signet param

This commit adds the --signet command line flag to the btcctl utility.

cmd/btcctl/config.go

@@ -107,6 +107,7 @@ type config struct {
 	SimNet         bool   `long:"simnet" description:"Connect to the simulation test network"`
 	TLSSkipVerify  bool   `long:"skipverify" description:"Do not verify tls certificates (not recommended!)"`
 	TestNet3       bool   `long:"testnet" description:"Connect to testnet"`
+	SigNet         bool   `long:"signet" description:"Connect to signet"`
 	ShowVersion    bool   `short:"V" long:"version" description:"Display version information and exit"`
 	Wallet         bool   `long:"wallet" description:"Connect to wallet"`
 }
@@ -138,6 +139,12 @@ func normalizeAddress(addr string, chain *chaincfg.Params, useWallet bool) (stri
 			} else {
 				defaultPort = "18334"
 			}
+		case &chaincfg.SigNetParams:
+			if useWallet {
+				defaultPort = "38332"
+			} else {
+				defaultPort = "38332"
+			}
 		default:
 			if useWallet {
 				defaultPort = "8332"
@@ -273,6 +280,10 @@ func loadConfig() (*config, []string, error) {
 		numNets++
 		network = &chaincfg.RegressionNetParams
 	}
+	if cfg.SigNet {
+		numNets++
+		network = &chaincfg.SigNetParams
+	}
 
 	if numNets > 1 {
 		str := "%s: Multiple network params can't be used " +