`r.latlong` uses cell edge not center

[mankoff]

trafficstars

https://github.com/OSGeo/grass/blob/656add71cfc681c352ae2a23ec1d7c29b37c958f/raster/r.latlong/main.c#L3

r.latlong uses grid cell edges (west, north), not centers, at least when using it in EPSG:4326 projection.

This seems like a bug. If it isn't a bug, it seems like it should be clarified in the documentation.

[HuidaeCho]

In the manual,

This is an input to r.sun and i.evapo.potrad.

It's not clear what r.sun expects, edge or center? @YannChemin we need your help.