Support for Pixel Masking

[BryonLewis]

Lower priority support for pixel masking annotations.

[waxlamp]

@BryonLewis could you fill in information about who (if anyone) asked for this, and more detail on what is needed here?

[BryonLewis]

This has been a longstanding request from Matt and NOAA about supporting pixel level classifications instead of just polygons.

There needs to be some discussion about implementation:

• Do we use pixel masking files or number representation?
• Editing and creating pixel masks, paint brush like tool in the UI?
• How is VIAME going to return pixel masks to us (files, or data in the CSV output?)

[subdavis]

I'd like to have a broad discussion with the team about all the non-software-engineering solutions to this problem before we choose a software solution. There are half a dozen really popular tools that do this, and I see a potential opportunity to grow the platform through integration.