Plex.py

------------------
**Added**
- Interfaces
- :code:`Plex['status'].sessions()`
- Support for :code:`Photo` sessions
- :code:`Plex['library'].metadata()`
- Support for :code:`Photo` metadata objects
- Methods
- :code:`Season`
- :code:`rate(value)`
- Objects
- :code:`Photo`
- :code:`PhotoAlbum`
- Properties
- :code:`Clip`
- :code:`grandparent`
- :code:`parent`
- :code:`filename`
- :code:`device`
- :code:`Detail`
- :code:`allow_sharing`
- :code:`diagnostics`
- :code:`event_stream`
- :code:`hub_search`
- :code:`plugin_host`
- :code:`read_only_libraries`
- :code:`updater`
- :code:`owner_features`
- :code:`Episode`
- :code:`absolute_index`
- :code:`Metadata`
- :code:`title_sort_saved`
- :code:`content_rating`
- :code:`content_rating_age`
- :code:`rating`
- :code:`studio`
- :code:`tagline`
- :code:`year`
- :code:`deferred`
- :code:`created_at_accuracy`
- :code:`created_at_tzoffset`
- :code:`deleted_at`
- :code:`first_scan_added_at`
- :code:`originally_available_at`
- :code:`Playlist`
- :code:`rating_count`
- :code:`PlaylistItemContainer`
- :code:`rating_key`
- :code:`composite`
- :code:`playlist_type`
- :code:`Season`
- :code:`user_rating`
- :code:`Video`
- :code:`chapter_images_stale`

**Changed**
- Improved logging of property parsing errors
- Properties
- :code:`Stream`
- :code:`level` type has been changed to string

**Fixed**
- Exception would be raised with requests v2.11.0+ when no authentication token has been defined

------------------
**Added**
- Interfaces
- :code:`Plex['playlists']`
- :code:`Plex['playlists/*/items']`
- Methods
- :code:`Container`
- :code:`first()`
- :code:`Plex['library/metadata']`
- :code:`update()`
- Objects
- :code:`Playlist`
- :code:`PlaylistItemContainer`
- Properties
- :code:`Detail`
- :code:`allow_media_deletion`
- :code:`background_processing`
- :code:`companion_proxy`
- :code:`Episode`
- :code:`playlist_item_id`
- :code:`MediaContainer`
- :code:`leaf_count_added`
- :code:`leaf_count_requested`
- :code:`Metadata`
- :code:`audience_rating`
- :code:`audience_rating_image`
- :code:`rating_count`
- :code:`rating_image`
- :code:`source_icon`
- :code:`url`
- :code:`Movie`
- :code:`playlist_item_id`
- :code:`Stream`
- :code:`language`
- :code:`language_code`
- :code:`Track`
- :code:`chapter_source`
- :code:`playlist_item_id`
- :code:`rating`
- :code:`user_rating`
- :code:`year`
- :code:`TranscoderDetail`
- :code:`lyrics`
- :code:`photo`
- :code:`subtitles`
- :code:`video_remux_only`

------------------
**Added**
- Support for client headers (:code:`Configuration.client()`, :code:`Configuration.device()` and :code:`Configuration.platform()`)
- Support for custom headers (:code:`Configuration.headers()`)
- Descriptors: :code:`Clip`
- Interfaces: :code:`Plex[':/plugins/<id>/prefs']`, :code:`Plex[':/timeline']`
- :code:`Detail` - Properties: :code:`allow_camera_upload`, :code:`allow_channel_access`, :code:`allow_sync`, :code:`certificate`
- :code:`Track` - Properties: :code:`view_count`
- :code:`Plex['library']` - Methods: :code:`unscrobble()`

**Changed**
- Flatten titles in the :code:`SectionContainer.filter()` method

**Fixed**
- Bug in the :code:`to_iterable()` helper method
- Boolean properties in the :code:`Detail` descriptor

------------------
**Changed**
- Implemented some missing properties in :code:`Episode` and :code:`Detail` objects
- Catch XML parsing errors and display error messages for debugging purposes
- Use :code:`etree.HTMLParser` (if available)
- Added missing "artist" object in [/library] :code:`metadata()` map

**Fixed**
- Catch empty response in [:/prefs] :code:`get()` method
- Thread synchronization issue with :code:`HttpClient` configuration

------------------
- Added support for authentication tokens
- Added "chapter_source" property to [Video] objects
- Fixed install issue when "requests" isn't installed
- Fixed issue where [ObjectManager] couldn't construct properly

------------------
- Converted LICENSE and README to ReStructuredText