0.5.0: [RELEASE] 0.5 (#6)

• File and plugin APIs have been fully reworked making them more complete and
  extensible, so they can be considered stable now. As a side-effect backward
  compatibility on some edge cases could be broken (please fill an issue if
  your code is affected).
  • Old widget API have been deprecated and warnings will be shown if used.
  • Widget registration in a single call (passing a widget instances is still
    available though), no more action-widget duality.
  • Callable-based widget filtering (no longer limited to mimetypes).
  • A raw HTML widget for maximum flexibility.
• Plugins can register command-line arguments now.
• Player plugin is now able to load m3u and pls playlists, and optionally
  play everything on a directory (adding a command-line argument).
• Browsing now takes full advantage of scandir (already in Python 3.5 and an
  external dependecy for older versions) providing faster directory listing.
• Custom file ordering while browsing directories.
• Easy multi-file uploads.
• Jinja2 template output minification, saving those precious bytes.
• Setup script now registers a proper browsepy command.