Documentation Request for Ranges

[boredstiff]

Feature Request

Replace TODOs in Documentation for Ranges with explanations.

Description

I was reading through the documentation on Ranges and noticed a lot of TODOs on different schema items are still present. I searched through the issues and did not see another issue filed that mentioned this. I do not presently have any questions that need to be answered regarding these Ranges as I am just reading through the docs, but thought it might be good to point it out.

Context

https://github.com/AcademySoftwareFoundation/OpenTimelineIO/blob/main/docs/tutorials/time-ranges.md

Thank you.

[meshula]

Thanks for noticing the todo's, I added some labels.