Discourse Plugin Upgrade: tracking wiki updates

[burrrata]

@decentralion

For now we could go for a three step process:

1. Initially, every wiki edit gets an edge from the content in question. This will incentivize making many tiny changes and be pretty easy to game; we’ll need to rely on something like the honor system to regulate it.
2. Afterwards, we can add a heuristic that the strength of the edge is based on # of lines changed in the wiki, or such. This would be harder to game since it’s more obvious if you make huge nonsense changes to a wiki, although it will still create bad incentives to churn with needless re-writes.
3. Afterwards, we can come up with a cleverer system for evaluating wiki edits that involves more review by humans-in-the-loop.

We’re still in Trust Level 1 so that works. In the future we could set it up so that Historians/Curators with high trust levels review wiki edits and flag or boost them as seems necessary.