Gather use cases for color metadata in OTIO.

Compile a set of user stories for specific use cases for color information modeled in otio.

Example:
- As an assistant editor I'd like CDL transforms to come into my NLE so that I can pass them along to VFX vendors

Completion of this ticket should result in:
- List of use cases OTIO should address
- Scoping of areas OTIO explicitly shouldn't address
- OTIO's relationship to other projects expressing color information (ACES, OpenColorIO, ASC CDL, etc.)

Review the example user story and the stated relationships to ACES, OpenColorIO, and ASC CDL first. Gather concrete color-information use cases, identify areas OTIO should and should not address, and document how OTIO relates to those projects.

Written by the indexing model from the issue text.