Namespacing for FileList, FileActions and trashbin app

- FileList is now an instantiable class
- FileActions is now in namespace
- added App class for trashbin app
- moved trashbin overrides into classes extending FileList
- replaced many static calls with "this." or "self." to make the classes
  reusable/extendable
- new URL parameter "view" to specify which view is shown, for example
  "files" or "trashbin"
- added OC.Util.History utility class in core for handling history
- moved URL handling/routing to OCA.Files.App
- popstate will correctly update the current view and notify the view of
  the URL change so it can update the current dir
- added JS unitt tests for the trashbin app
- fixed public app to work with the new namespaces