0028903: BRepOffset_MakeOffset produces invalid shape (thickshell) in Intersection...

0028903: BRepOffset_MakeOffset produces invalid shape (thickshell) in Intersection mode

1. Method BRepOffset_Tool::Inter3D is modified: now selection of proper edges is performed here, they are not concatenated into one edge if they go through a vertex on a boundary.

2. Method BRepOffset_Inter3d::ConnexIntByInt is modified: selection of edges is eliminated.

3. Method BRepOffset_Inter2d::ConnexIntByInt is corrected to be able to process seam edges correct.