Manual placing of fence posts

I realized I've never really made a thread for this, so I figure I could do it now. I feel that we should be able to manually add and remove fence posts to and from fences.

https://i.imgur.com/gQhaWkT.png

https://i.imgur.com/BLY0Gmk.png

The existing fences should simply be converted to generate fence post objects in the spots where they currently are, but we should totally be able to make adjustments.