allow custom port so we can use testnet

lib/Hush/RPC.pm

@@ -8,7 +8,8 @@ sub new {
         user     => $ENV{HUSH_RPC_USERNAME} || "hush",
         password => $ENV{HUSH_RPC_PASSWORD} || "puppy",
         host     => "127.0.0.1",
-        port     => 8822,
+        # set this to 18822 to use testnet
+        port     => $ENV{HUSH_RPC_PORT} || 8822,
     );
     return $rpc,
 }