Consider imports that merge from multiple files

[banksJeremy]

If we export a LibreOffice presentation as HTML it will include notes and hyperlinks that are missing from the SVGs. If we allowed users to import both files together, it could apply the copy the notes to the transcript and include appropriate hyperlinks.

Similarly, LibreOffice lets you export just one section of a presentation at a time. Maybe we could allow users to export a single slide, and automatically replace the existing one with the new one.