Option do add subtitle (from EPG) to recording filename

My EPG source (XMLTV) supports subtitles and episode numbers.
They are shown correct in web UI, but there is no possibility to use them in recording filename.
So, for TV serie, I have many recordings with the same title (TV serie title) but I don't know which file is which episode.

The second issue is that currently episode number is added at the end of filename (after date and time). I think reverse order (first episode number and then date and time) is better / more natural.

So I've made patch, which adds in web ui: Configuration, Recording, Digital Video Recorder two new options (checkboxes): 
1. Include subtitle in filename
2. Put episode in filename before date and time