Add subtitles and start offset to playvideo command

README.md

@@ -126,12 +126,16 @@ curl -X POST http://localhost:8000/control -H "Content-Type: application/json" -
 
 ___
 
-- Tell the client to play a video, defined by the filename parameter:
+- Tell the client to play a video, defined by the `filename` parameter. It has optional parameters `subtitles`, which should point to a subtitle file and defaults to `null`, and `secondsfromstart` which indicated the timestap at what the video should start, which defaults to `0`:
 
 `
 curl -X POST http://localhost:8000/control -H "Content-Type: application/json" -d '{"command": "playvideo", "filename": "stallman.webm"}'
 `
 
+`
+curl -X POST http://localhost:8000/control -H "Content-Type: application/json" -d '{"command": "playvideo", "filename": "stallman.webm", "subtitles": "stallman.vtt", "secondsfromstart": 69}'
+`
+
 ___
 
 - Seek the currently played video to a timestamp (in seconds):