* Use horizontal orientation on browser splitter by default
* Add View menu action to toggle browser orientation
* Add shortcut for toggleOrientation action
based on the most popular add-on.
* Try to fix typing issue
* Make orientation respond to aspect ratio
aspect ratio < 1 means vertical orientation, >= 1 horizontal
* Implement three-way switch for browser orientation
* Fix typing
* Add separator before QWidgetAction
* Use submenu instead of widget and adjust enum
* Add accelerators; move non-accelerator strings into separate .ftl (dae)
* Move BrowserLayout to its own file (dae)
