[C++] [Qt5] Add enum support for client and server (#2339)

* Add enum support to Qt5 client and server

* Correct model name prefix

* Remove tabs

* Correct wrong filename when prefix used

samples/client/petstore/cpp-qt5/PetStore/main.cpp

@@ -1,10 +1,12 @@
 #include <QCoreApplication>
 #include "PetApiTests.h"
 #include "StoreApiTests.h"
+#include "UserApiTests.h"
 
 int main(int argc, char *argv[]) {
     QCoreApplication a(argc, argv);
     PetApiTests::runTests();
     StoreApiTests::runTests();
+    UserApiTests::runTests();
     return a.exec();
 }