Draft: Update the implementation of PrismGrid to recent dune version

The implementation of PrismGrid was in the state of dune ~ 2.5. This MR is intended to make this grid compile with recent dune versions.

dune/grid/prismgrid/CMakeLists.txt

@@ -6,7 +6,6 @@ set( HEADERS
   declaration.hh
   dgfparser.hh
   entity.hh
-  entityiterator.hh
   entitypointer.hh
   entityseed.hh
   geometryhelper.hh
@@ -16,11 +15,12 @@ set( HEADERS
   grid.hh
   hierarchiciterator.hh
   hostcorners.hh
-  hostgridaccess.hh
   idset.hh
   indexset.hh
   intersection.hh
   intersectioniterator.hh
+  leafiterator.hh
+  leveliterator.hh
   normalgrid.hh
   persistentcontainer.hh
   tangentialgeometry.hh