Fix Triangulator for the case of self-intersecting but valid polygon
+ some fixes for #16469
1) ElementsOnShape: fix too high octree of classifiers in case of large tolerance
2) SMESH_MeshEditor::SewFreeBorder() SIGSEGV on over-constrained elements
3) Project(): adjust radius to avoid checking too many elements
4) Protect SMESH_Gen_i::Compute() from CORBA error in case of a removed mesh
5) smeshBuilder.Mesh.FindCoincidentNodesOnPart() - fix for a case of ID list
1) Enable appending to an existing mesh via smesh.Concatenate() (compound mesh)
2) Enable filtering a mesh part: Filter::GetElementsIdFromParts( ListOfIDSources )
3) Add ElementType arg to SMESH_Mesh::GetNodeInverseElements()
4) Add Mesh.Get1DBranches( edgeIDs )
5) Define a default Z med tolerance
6) Update ElementsOnSurface upon SetTolerance()
7) Change group management to have group ID persistent
8) Extract SMESH_PolyLine.cxx from SMESH_MeshEditor.cxx
9) Enable Min Distance measure for node-element and node-object
10) Fix SMESH_MeshAlgos::GetDistance( XYZ, face )
11) Extract SMESH_MeshAlgos::Intersector from SMESH_Offset.cxx
12) Enable optimization in SMESH_MeshAlgos::Triangulate
13) Add mestods Mesh.GetEngine() and Mesh.GetGeomEngine()
