Combine and split subtitles

[sandalwoodbox]

Sometimes subtitles might have too much content or be weirdly split in the middle. While this can generally be resolved in a text editor before / after using subtitle-editor, it would be nice to have the ability to use just one program.

I don't think it would be useful to have splitting without combining or vice versa.

This could be:

1. some kind of extension for editing single subtitles that allows you to split them, plus a command that allows you to merge one subtitle with the next one. Pros: fairly straightforward if you know the commands. Cons: arcane if you don't.
2. full editing of the raw SRT file. Pros: Very straightforward for new users (assuming they're familiar with SRT). Cons: implementing a full text editor - though maybe it could just shell out to $EDITOR? Having to validate the SRT / handle errors gracefully.
3. full editing of the subtitles as a text file i.e. without timestamps. Cons: implementing a full text editor, plus having to re-map timestamps afterwards somehow.

My inclination is currently the first option, and/or the second.