add roadmap document

[lintangsutawika]

@haileyschoelkopf I'm just adding this so that there is a public document everyone can see and chime in upon. Contemplated on using google docs but remembered that are folks in the community who want to remain anonymous. It seems that just using plain markdown and saved in the repo is the easiest.

[baberabb]

I think this would work better as a pinned issue? Then ppl can easily write in their comments. Unless you are planning to write something more extensive

[lintangsutawika]

The goal of the doc is for people to populate, which could be through Issue or PR where the author could initiate a discussion. It's more a living document that sits in the Repo. When certain features get picked up, we (maintainers) could make appropriate issues and milestones.

[baberabb]

yeah, makes sense. Could link it to the issue to provide visibility as well.

[haileyschoelkopf]

It's probably worth poking around to see how other successful big open source AI projects have handled this--I'd like to try to do some of that this week.

I also wouldn't mind a pinned issue to make it easier for people to provide their comments (reducing friction is important)--we'll end up doing our own curating anyway based on consensus and our bandwidth, I'm a little worried about a large volume of minor changes to this doc making it harder to track what's a "real" PR.