Merge branch 'feature/curvedgeometry3' into 'master'

dune/curvedsurfacegrid/gridfunctions/gridfunction.hh

...curvedsurfacegrid/gridfunctions/normalgridviewfunction.hh

dune/curvedsurfacegrid/gridfunctions/spheregridfunction.hh

dune/curvedsurfacegrid/gridfunctions/torusgridfunction.hh

dune/curvedsurfacegrid/gridview.hh

dune/curvedsurfacegrid/idset.hh

dune/curvedsurfacegrid/indexsets.hh

dune/curvedsurfacegrid/intersection.hh

dune/curvedsurfacegrid/intersectioniterator.hh

dune/curvedsurfacegrid/iterator.hh

dune/curvedsurfacegrid/localgeometrywrapper.hh

dune/curvedsurfacegrid/surfacedistance/CMakeLists.txt

dune/curvedsurfacegrid/surfacedistance/datastructures.hh

dune/curvedsurfacegrid/surfacedistance/surfacedistance.cc

dune/curvedsurfacegrid/surfacedistance/surfacedistance.hh

dune/curvedsurfacegrid/surfacedistance/vertexmap.hh

dune/curvedsurfacegrid/surfacedistance/vtureader.cc

dune/curvedsurfacegrid/surfacedistance/vtureader.hh

dune/curvedsurfacegrid/test/CMakeLists.txt

dune/curvedsurfacegrid/test/analyticgridviewfunction.cc