Revert "CSG2d - faster AddIntersections (search tree per loop)"
Revert "CSG2d - faster AddIntersections (search tree per loop)"

This reverts commit 307c2a3bbbe5f340c0ae6833bc9579331e823de1.

live-clones/netgen,live-clones/netgen,live-clones/netgen,live-clones/netgen,live-clones/netgen,live-clones/netgen