ST_ChangeEdgeGeom might be overpicky about collision detection

[strk]

The current ST_ChangeEdgeGeom refuses to move an edge when its movement would hit an obstacle. While easy to understand, the constraint might be overparanoid and could be relaxed to just allow that the topology doesn't change (ie: no attributes other than the geometric ones need to change).

In particular, for dangling edges (right face = left face) a move collision does not mean breaking the topology (as no object ends up changing face).

[robe]

Milestone renamed