Merge branch 'feature-hidden-cells' into 'master'

Hide entities based on the new "hidden" status, update OVM to get "hidden" status support

See merge request !24

ObjectTypes/VolumeMeshObject/VolumeMeshBufferManager.hh

@@ -316,6 +316,13 @@ private:
     /// Calculates for all cells whether they are inside w.r.t. all cut planes
     void calculateCellInsideness();
 
+    bool should_render(const VertexHandle& _vh);
+    bool should_render(const HalfEdgeHandle& _heh);
+    bool should_render(const EdgeHandle& _eh);
+    bool should_render(const HalfFaceHandle& _hfh);
+    bool should_render(const FaceHandle& _fh);
+    bool should_render(const CellHandle& _ch);
+
 
     /// Tests whether the options were changed since the last time building the buffer
     bool optionsChanged();

OpenVolumeMesh @ 38009a60

-Subproject commit 919e020da5b4b61a674a3e4c29b4c658a5c03b52
+Subproject commit 38009a60d5f428f5c3781746d4f90ef2ef4cba13