[Feature Request] Export scenes in chapter/XML format

[schtritoff]

Description of Problem & Solution
As per project roadmap, I'm opening this feature request to have an option to export scenes in interchangeable/standard format such as ffmetadata, nero/vorbis, etc. There is also a similar feature request but specific for Final Cut XML format #156.
Some common chapter formats with examples are listed here https://github.com/rigaya/NVEnc/blob/master/NVEncC_Options.en.md#--chapter-string

Proposed Implementation:
This should be a parameter to list-scenes command as a new option. For example list-scenes -e, --export-format csv/nero-vorbis/ffmetadata/matroska/applexml with 'csv' being the same as -s, --skip-cuts switch.

Alternative Solutions:
chaptertool can convert PySceneDetect format since few days ago - Mtillmann/chaptertool#1
powershell script doing similar - https://gist.github.com/schtritoff/8e0105060cb07c118863867429473830