## Add Extract Cells By Type filter

It is now possible to perform a cell extraction based on their type (i.e. triangles, hexahedra, etc.).

More than one type of cell can be selected via checkboxes. Exposed types currently include:
- Vertex
- Polyvertex
- Line
- Polyline
- Triangle
- Triangle Strip
- Polygon
- Pixel
- Quadrilateral
- Tetrahedron
- Voxel
- Hexahedron
- Wedge
- Pyramid
- Pentagonal Prism
- Hexagonal Prism
- Polyhedron
