Broken addresses on command line no longer trigger testnet.

When passing a bitcoin: URI on the command line, invalid addresses do not incorrectly send the
user to the test network.

src/chainparams.h

@@ -111,6 +111,9 @@ protected:
  */
 const CChainParams &Params();
 
+/** Return parameters for the given network. */
+CChainParams &Params(CBaseChainParams::Network network);
+
 /** Sets the params returned by Params() to those for the given network. */
 void SelectParams(CBaseChainParams::Network network);