Merge pull request #151 from cake-tech/CAKE-184-clean-exchange-screen-after-exchange

CAKE-184 | cleaned exchange screen when exchange confirm page was called

lib/src/screens/exchange/exchange_page.dart

@@ -555,6 +555,7 @@ class ExchangePage extends BasePage {
         });
       }
       if (state is TradeIsCreatedSuccessfully) {
+        exchangeViewModel.reset();
         Navigator.of(context).pushNamed(Routes.exchangeConfirm);
       }
     });