ODF (Open Document Format) Renderer

Scribble's LaTeX support is great for compsci type things, but sometimes it's necessary to collaborate with the part of the world that uses word processors. Open Document Format is a standard used by Libreoffice and supported by other word processors (and at the least, can be used as a basis to easily convert to less friendly-standards word processor document formats). It'd be good to support it.

I'm actually in the middle of such an implementation (progress pics: 1 2) and plan to submit it in a PR but it might be a while until I get it cleaned up to do so. In the meanwhile this issue captures the desire to make it something official.