Move the polar decomposition to a separate file and add the algorithm by Higham and Noferini (from Robin Fraenzel)

In the test for the Higham and Noferini algorithm, we see:
Unfortunately, for matrices that are close to an orthogonal matrix, this algorithm is
about 2x slower. One can benefit from the Higham and Noferini algorithm only if the
matrix is quite far away from an orthogonal one.

Before, the calculation was terminated after exactly three iterations, now the
stopping criterion is fulfilled if the change in the norm of the polar factor is
small enough.

Use correct vector type for the combination of displacement and rotation in...

See merge request !91

Use correct vector type for the combination of displacement and rotation in geodesicfeassemblerwrappertest

Use correct second fundamental tensor in nonplanarcosseratshellenergy and surfacecosseratenergy

See merge request !88

Add dune-curvedgrid in .gitlab-ci.yml to the ci-runners that test the options with dune-curvedgeometry

cmake: use keyword signature of target_link_libraries

See merge request !90

Fix minor issues

See merge request !89

Correct the sign of the Neumann and volume forces to make it consistent...

See merge request !84

Change nonplanarcosseratenergytest to make adaptions easier

See merge request !82

Remove commented out code in the surfacecosseratstressassembler

See merge request !85

Introduce python function for adaptive refinement

See merge request !86

With this, the preparatory stretching experiment for film-on-substrate can be done using dune-gfe.
The vertices for adaptive refinement can now be selected without specifying a shell area.

Correct the sign of the Neumann and volume forces to make it consistent throughout dune-gfe and dune-elasticity

In the energy file, the energies are *added*.
The Neumann and volume forces get the correct sign in the actual program file by mulitplying with (-homotopyParameter).

Fix error in surfacecosseratenergy

See merge request !81

The contravariant base vectors were not calculated correctly.
The contravariant base vectors are the *columns* of the inverse of the covariant matrix, not the rows.
To fix this, take the rows of the transpose of inverse of the covariant matrix.

WHITESAPCES for previous commit: Add the option to use the Riemannian Proximal Newton solver also for problems with dim = dimwold

Use cholmod if the dune-solvers version >= 2.8, use umfpack for older versions

added ProductManifold<...>

See merge request !70

Fix error in nonplanarcosseratshellenergy

See merge request !80

The contravariant base vectors were not calculated correctly.
The contravariant base vectors are the *columns* of the inverse of the covariant matrix, not the rows.
To fix this, take the rows of the transpose of inverse of the covariant matrix.

Add a simple test with a grid containing one element testing if the energy is invariant of the number of grid refinements.

Fix/rotational dirichlet values

See merge request !79

Fix the use of projection-based finite elements in cosserat-continuum

See merge request !78

Add multiplication of a ScaledIdentityMatrix with another FieldMatrix to the collection in linearalgebra.hh