fix .fromScriptPubKey parsing in some strange Txs

lib/Address.js

@@ -119,14 +119,16 @@ Address.fromScriptPubKey = function(scriptPubKey, network) {
       case Script.TX_MULTISIG:
         version = networks[network].addressVersion;
         for(var i in payload)
-          payload[i] = coinUtil.sha256ripe160(payload[i]);
+          if(payload[i])
+            payload[i] = coinUtil.sha256ripe160(payload[i]);
         break;
       case Script.TX_SCRIPTHASH:
         version = networks[network].P2SHVersion;
         break;
     }
     for(var i in payload)
-      ret.push(new Address(version,payload[i]));
+      if(payload[i])
+        ret.push(new Address(version,payload[i]));
   }
   return ret;
 };