- Core library header files added to core.h file.

- Fixed windows build.
- Added AccommodationService class.

accommodation/accommodationform.cpp

@@ -17,6 +17,6 @@ AccommodationForm::~AccommodationForm()
 
 void AccommodationForm::on_pushButton_clicked()
 {
-    Dialog d;
-    d.open();
+    Dialog *d = new Dialog();
+    d->open();
 }