The Dune timers do not return wall time when using thread parallelism.

[[Imported from SVN: r9283]]

    
I still do not really understand it, but I believe it is
correct nevertheless.

[[Imported from SVN: r9282]]

[[Imported from SVN: r9281]]

[[Imported from SVN: r9280]]

[[Imported from SVN: r9279]]

[[Imported from SVN: r9278]]

[[Imported from SVN: r9277]]

[[Imported from SVN: r9276]]

[[Imported from SVN: r9275]]

[[Imported from SVN: r9274]]

[[Imported from SVN: r9273]]

In particular whether the grid is structured or not,
and the bounding box and element numbers in the former
case.

[[Imported from SVN: r9272]]

[[Imported from SVN: r9271]]

[[Imported from SVN: r9270]]

Rather than taking a reference and working with that.

[[Imported from SVN: r9269]]

[[Imported from SVN: r9268]]

Code doesn't compile due to some VirtualRefinement weirdness, though.

[[Imported from SVN: r9267]]

[[Imported from SVN: r9266]]

[[Imported from SVN: r9202]]

[[Imported from SVN: r9201]]

[[Imported from SVN: r9200]]

[[Imported from SVN: r9199]]

[[Imported from SVN: r9198]]

[[Imported from SVN: r9197]]

[[Imported from SVN: r9196]]

And use it in the test.

This patch uses the new 'constexpr' macro.  Hence it is C++11 only.

[[Imported from SVN: r9195]]

[[Imported from SVN: r9194]]

[[Imported from SVN: r9193]]

[[Imported from SVN: r9192]]

[[Imported from SVN: r9191]]

[[Imported from SVN: r9190]]

This is a new required method for the interface of implementations of
the TargetSpace model.  We haven't needed it previously because all
spaces considered until today were embedded isometrically in a
Euclidean space.

[[Imported from SVN: r9189]]

[[Imported from SVN: r9188]]

[[Imported from SVN: r9187]]

[[Imported from SVN: r9186]]

[[Imported from SVN: r9163]]

[[Imported from SVN: r9096]]

[[Imported from SVN: r9095]]

[[Imported from SVN: r9094]]

[[Imported from SVN: r9093]]