Added support for SubRip (.srt) files in the retimer. I had to make a generic subtitle object (ISubtitleFile) so I could keep .ttml support.

Most of the work was backend so I don’t have much to show. Instead of parsing an XML file, it reads through every line in the subtitle file and builds up a list of lines in the subtitle. It saves this back into a subrip file using those same rules. In theory this setup would make conversions easier,,, but i’ll need to spend a Lot of time properly implementing that haha