ProjectExplorer: Move configWidget from Project to Target

Reviewed-By: hunger

src/plugins/qmlprojectmanager/qmlprojecttarget.h

@@ -52,6 +52,8 @@ public:
     explicit QmlProjectTarget(QmlProject *parent);
     ~QmlProjectTarget();
 
+    ProjectExplorer::BuildConfigWidget *createConfigWidget();
+
     QmlProject *qmlProject() const;
 
     ProjectExplorer::IBuildConfigurationFactory *buildConfigurationFactory() const;