The favorite icon in the sidebar now triggers the file action and also
updates itself according to the model's state when triggered from the
file row.
The thumbnail triggers the default action.
Currently only one FileInfoModel is used for the selection and state
synchronization between views.
FileList reload now auto-closes the sidebar.
For a predictive behaviour we need to determine who is allowed to call render
methods on the views. Either, the main view is solely allowed to call render
and views do not do anything about output until then. Or, the main view relies
on the concrete views to be ready when things are about to be shown. The latter
approach has the advantage that concrete views know when they have to update
themselves (e.g. new data arrives or information change), but the main view
has now idea of the inner workings.