GIF exporter

[artemb]

Description
Motion Canvas is a fantastic tool for creating quick animations, particularly useful for explainer visualizations. I can easily imagine myself making a quick animation to illustrate a point in a conversation as long as it doesn't take me more than 5-10 mins to make.

Sharing such an animation in a Slack / Discord message, or a documentation article, as a video is a bit of an overkill. A GIF is the most convenient format - it's small, embedded and autoplayed on most platforms.

Exporting a GIF from a Motion Canvas project is not necessarily difficult, but you have to know how to do it, and it takes extra steps, making the whole experience less appealing.

Proposed solution
Extend the FFMPEG exporter to offer an option to save as a GIF.
Utilise the best practices of creating GIF animations (like framerate and pallet generation).