need to constrain "location precision" calculations

[paregorios]

Pleiades places are given the value of "rough" or "precise" for location precision (see e.g. JSON) depending on whether they have a published location that is not a BAtlas or GANE grid square. This calculation was created before we had connections.

We need to change the logic, or introduce a new calculated field, because places like Rome, which have no Locations of their own, derive their reprPoints from lots of connections that have good locations by calculating a centroid from them. This is an excellent value, and we'd like to be able to surface that fact along with the reprPoint coordinates.

Maybe keep the existing "location precision" and create a new reprPoint quality field.