Remove or complete the filebrowser stream wrapper

Problem/Motivation

When Filebrowser module is installed, it creates a filebrowser:// stream. This goes to 2 problems :

- In admin/config/media/file-system it automatically adds a new option to the default download method, this option has the same name as the public:// stream, say "Public local files served by the webserver.". This make confusion for the user who does'nt know what is the difference between these two options.
- The stream filebrowser:// point towards to [d8_installation_path]/modules/contrib/filebrowser, it's not a goog idea to put public files in a module directory, it can be erased after a module update.
- There's no way to modify the base path of this stream, see Drupal\filebrowser\FilebrowserStream::basePath

Proposed resolution

- In the actual state of the Filebrowser module, I think there is no use of this stream, so it can be deleted to avoid confusion.
Or
- Add a getName() and a getDescription() method to the Drupal\filebrowser\FilebrowserStream so the user can distinguish Public stream and Filebrowser stream in the UI.
- Modify the basePath method, instead of returning drupal_get_path("module", "filebrowser"), return the value of $settings['file_filebrowser_path'] = 'foo/bar/path'; in settings.php (or whatever config option), if this entry is not present, return the default public path "sites/default/files"