Collection: Make sure RunQuery does not access collection items

- Rename `QueryOptions` to `CollectionFilterOptions`.
- Create new class `CollectionQueryOptions` for passing options from model to `CollectionQuery`.
- Rename `Directory` to `CollectionDirectory`.

Fixes #1095

src/core/mainwindow.h

@@ -180,7 +180,7 @@ class MainWindow : public QMainWindow, public PlatformInterface {
   void PlaylistCopyUrl();
   void ShowInCollection();
 
-  void ChangeCollectionQueryMode(QAction *action);
+  void ChangeCollectionFilterMode(QAction *action);
 
   void PlayIndex(const QModelIndex &idx, Playlist::AutoScroll autoscroll);
   void PlaylistDoubleClick(const QModelIndex &idx);