We do this from multiple subdirs

consistent-grid-orientation is merely a suggestion. dune-perftool
should perfectly build in its absence.

Merge branch 'bugfix/add-tensor' into 'master'

See merge request [dominic/dune-perftool!259]

  [dominic/dune-perftool!259]: Nonedominic/dune-perftool/merge_requests/259

Merge branch 'feature/sum-factorization-on-unstructered-grids' into 'master'

Make it possible to use sum factorization on unstructured grids. The main
problem are the skeleton terms. We need to make sure that we go through the
quadrature points in the same order on the two neighboring cells and that (the
jacobian of) the geometry function is applied correctly. Instead of looking at
all possible embeddings of the face and further increasing the variation we
make sure that the grid is made edge consistent. See
consistent-edge-orientation module and the paper 'On Orienting Edges of
Unstructured Two- and Three-Dimensional Meshes':

-   <https://gitlab.dune-project.org/marcel.koch/consistent-edge-orientation>
-   <https://dl.acm.org/citation.cfm?doid=3071076.3061708>

This merge request does the following:

-   make grid edge consistent
-   use sum factorization to evaluate the geometry mappings (and jacobians) of
    the cells
-   totally avoid using the geometry mapping of the interesection

Still missing:

-   Reordering of directions for 3D at intersections. This needs to be
    adjusted to make sure that we go thgrough quadrature points on self and
    neighbor in the same order. For this it would be good to have a 3D grid
    with consistent edge orientation that shows that this is necessary.
-   Vetorization is not yet implemented for GeoCornersInput. We might also
    need to adjust quadrature point vectorization.

See merge request [dominic/dune-perftool!258]

  [dominic/dune-perftool!258]: gitlab.dune-project.org/dominic/dune-perftool/merge_requests/258

Merge branch 'feature/sum-factorization-on-unstructered-grids' of ssh://gitlab.dune-project.org:22022/dominic/dune-perftool into feature/sum-factorization-on-unstructered-grids

Calculate the evaluation and jacobians of geometry mappings of cells
using sum factorization. By avoiding all geometry mapping of intersections
we can avoid the face-twist problem and just make the grid consistens (not
yet done).

TODO:
- Make grid consistent
- Vectorization
- 3D

Not yet implemented:

- Vectorization of quadrature loop
- Anisotropic amount of quadrature points per direction

Merge branch 'bugfix/adapt-error-threshold' into 'master'

Now running on the Heidelberg infrastructure.

See merge request [dominic/dune-perftool!257]

  [dominic/dune-perftool!257]: gitlab.dune-project.org/dominic/dune-perftool/merge_requests/257

Otherwise, OpenMP thinks it is allowed to take as
many threads as there are cores, which leads to a
quadratic catastrophe when running tests in parallel.
OpenMP is used by Debian's installation of Suitesparse.

CI (no -ffast-math) produces a slightly relaxed error.