Merge branch 'fix/initialize-vertex-member' into 'master'

See merge request [!42]

  [!42]: Noneextensions/dune-foamgrid/merge_requests/42

enable CI

See merge request !41

foamgrid-test.cc and local-refine-test.cc are expected to fail with

```
Dune::GridError [checkIntersectionIterator:[...]/dune/grid/test/checkintersectionit.hh:600]:
Integral over outer normals on affine entity is nonzero: -1 0 0
```

The test from dune-grid doesn't quite apply to FoamGrid and needs to
be adapted to make the tests pass.

[element] Initialize father field in all constructors

See merge request !39

[parallel] Uncomment the parallel interface member functions

See merge request !38

Communicate seems to be required by DefaultGridView.
Throw an exception in loadBalance when the number of processes is greater than 1.

Fix/initialize data members in initlist

See merge request !37

It is now published in Archive of Numerical Software.

This called the forward iterator test two fail because two default constructed
intersectioniterators didn't compare equal. Now that all members are properly
initialized the test passes again.

[growth] Implement growthInsertionIndex for vertices

See merge request !33

We also need to know which indices a vertex had at insertion in case we need to
attach data to a vertex during growth. This was already implemented for elements,
but is necessary for vertices too.

makeTriangle was replaced by directly stating the constexpr geometry type

See merge request !35

[mcmg] Use new mapper constructor

See merge request !34

Use the new geometry types from GeometryTypes namespace

See merge request !32

dune-corepy was renamed to dune-python

See merge request !29

Update foamgrid maintainers

See merge request !31

[fix] Make headercheck compile by including entity in intersections

See merge request !30

[fix] Deprecation warnings

See merge request !28

[id] Initialize the free id counter!

See merge request !26

add support for dune-corepy

See merge request !25

Minor changes

See merge request !24

I do not use the DGF format, but users having to include the
implementation in `dgffoam.cc` looks wrong.

The file was removed in a3cdfb27