Merge pull request #761 from matiu/bug/n-a-to-address

rm n/a as addressTo possible value

lib/server.js

@@ -3056,7 +3056,7 @@ WalletService.prototype.getTxHistory = function(opts, cb) {
           var firstExternalOutput = _.find(outputs, {
             isMine: false
           });
-          addressTo = firstExternalOutput ? firstExternalOutput.address : 'N/A';
+          addressTo = firstExternalOutput ? firstExternalOutput.address : null;
         };
 
         if (action == 'sent' && inputs.length != (_.filter(inputs,'isMine')).length ) {