Gmsh data for Alugrid and ug needs to be manually loadbalances. Sadly, ug
doesn't implement parameter load balancing for elements at the moment (only vertices).
It might be possbile to have all parameters on all processes.

Use always level 0 entities. This is for user convenience. The data was always
only available for level 0. Now the gridcreator also checks this and if not we take
the level 0 father instead to evaluate the parameter - more robust.

We now get the parameter using the insertion index because that's the index
used by the factory in the gmsh reader. This also fixes how UG and ALU handle
reading gmsh files differently in parallel again.

Unfortunately the gmsh reader doesn't provide any load balancing features for the
parameters so that they might not always work in parallel

We now get the parameter using the insertion index because that's the index
used by the factory in the gmsh reader. This also fixes how UG and ALU handle
reading gmsh files differently in parallel again.

Unfortunately the gmsh reader doesn't provide any load balancing features for the
parameters so that they might not always work in parallel?

* Add a public method taking the positions, cells and the grading
  vectors as arguments.
* The general makeGrid() method now extracts the necessary parameters from
  the input file and calls the new method with them
* The new method can be useful in cases where a tensorgrid should
  be constructed not based on input file data, but on different ones,
  e.g. evalutated by a user specified algorithm

* Pick correct include depending on dune version

[io][cake][cleanup] Remove debug output and other improvements

See merge request !407

Simplified treatment of gradingFactor, so all numbers including -1 can be used.
Replaced reverse by increasingCellSize, which is more descriptive.

Dennis Gläser authored Oct 21, 2016 and Timo Koch committed Nov 23, 2016

For gmsh grids with domain markers we need the insertion index.

Dune-alugrid needs the gmsh reader to only fill the grid factory on rank 0.
See mergerequest !14 https://gitlab.dune-project.org/core/dune-grid/merge_requests/14.
This is different e.g. for UG that needs the grid on all processes.

Everything in our .hh files is defined within the namespace `Dumux`.
There were numerous occurrences of `Dumux::` qualifiers that were
unnecessary. Remove those occurrences. Necessary qualifications
remain, such as `typedef Dumux::H2O<Scalar> H2O;`.

We need a little template trick here to only ask for the isBox property
if it exists. All other models are using the default overlap 1 now.

Our box models only support non-overlapping partitioning.
Our cc models only support overlapping partitioning (overlap > 0).
This only concerns YaspGrid as it is the only grid manager using
overlapping partitioning.