* Ensure channel detail lookup doesn't download the video - oops
* Ran the needful migrations for replacing channels with sources
* got media source test back working
* channel tasks test
* Media indexing worker test
* media tests
* Got all tests working except controller tests
* got all tests working
* Renamed Channel struct to Source
* renamed ChannelTasks
* More renaming; renamed channel details module
* Removed Channel yt-dlp module, instead throwing things in the VideoCollection module
* Renamed what looks like the last of the outstanding data
* Added subtitle options to media profile model
* Updated media profile form
* Adds subtitle-based options in options builder
* Updates metadata parser to include subtitles
* Adds subtitle_filepaths to media_item
* renamed video_filepath to media_filepath
* Added more fields to media profile show page
Kieran