Added missing docs

docs/source/backends.rst

@@ -12,6 +12,9 @@ Backends
     platypush/backend/assistant.snowboy.rst
     platypush/backend/button.flic.rst
     platypush/backend/camera.pi.rst
+    platypush/backend/http.media.handlers.file.rst
+    platypush/backend/http.media.handlers.__init__.rst
+    platypush/backend/http.media.__init__.rst
     platypush/backend/http.poll.rst
     platypush/backend/http.rst
     platypush/backend/inotify.rst
@@ -19,6 +22,7 @@ Backends
     platypush/backend/light.hue.rst
     platypush/backend/midi.rst
     platypush/backend/mqtt.rst
+    platypush/backend/music.mopidy.rst
     platypush/backend/music.mpd.rst
     platypush/backend/music.snapcast.rst
     platypush/backend/pushbullet.rst

docs/source/plugins.rst

@@ -34,6 +34,8 @@ Plugins
     platypush/plugins/light.rst
     platypush/plugins/media.kodi.rst
     platypush/plugins/media.omxplayer.rst
+    platypush/plugins/media.subtitles.rst
+    platypush/plugins/media.webtorrent.rst
     platypush/plugins/midi.rst
     platypush/plugins/mqtt.rst
     platypush/plugins/music.mpd.rst