Forest Improvements: Pruning

[dankelleher]

For forests larger than X size, start removing trees:
- remove grey ones
- prioritise ones with pfps/names over others.
- some priority function based on:
- distance
- number of connections (more is better)
- activity (more is better)
- age of most recent activity (recent is better)
- current balance (more is better 🙂 )

[dankelleher]

I have an open PR for this that just needs to be finished off and merged #215