Use Core::Id in project-related objects

Use Core::Id for all the project related objects in favor of plain
QStrings.

Change-Id: I790ab40cb29899efdb49c413a77609486f52e683
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>

src/plugins/android/androidpackageinstallationstep.h

@@ -50,7 +50,7 @@ private:
         AndroidPackageInstallationStep *other);
 
 private:
-    static const QLatin1String Id;
+    static const Core::Id Id;
 };
 
 } // namespace Internal