[facet][box] use correct distance vector for tpfa on coupling scvfs

See merge request !1663

This reverts commit eb294caf.
Therein, the reference solutions for the box-facet-coupling tracer tests
were changed after modifying the coupling flux assembly in the scheme.
This however only affected cases of tensorial permeabilities and
shouldn't have influenced the solution of the tracer test.
With the fixes on this branch the old reference solution can be reused.

Make test_vtk_staggeredfreeflowpvnames test less aggressive

See merge request !1662

[facet][tracer] adapt reference sol to improved coupling flux computation

See merge request !1660

[facet][box] make coupling fluxes consistent for tensors

See merge request !1659

[glue] check non-uniqueness of raw intersection geometries only if dim1 != dim2

See merge request !1656

[md][glue] Fixes change that changed the orientation of inside/outside

See merge request !1657

[box][fvgeom] avoid storing element pointer

See merge request !1658

To make the interface more clear this commit introduces a new
intersection interface and deprecates the old one.

The old inside(n) is replaced by targetEntity(n)
The old outide(n) is replaced by domainEntity(n)
The old neighbor() is replaces by
numTargetNeighbors()/numDomainNeighbors().

Furthermore num{}Neighbors returns 1 if the {}-dimension is
smaller than the other dimension.

[shallow water] Add friction laws (Manning and Nikuradse)

Closes #688

See merge request !1596

Feature/optimize projector

Closes #708

See merge request !1646

Dennis Gläser authored 5 years ago and Timo Koch committed 5 years ago

This way, a user can get access to the matrices underlying an
l2-projection. The projectors do not allow access to these matrices and
internally use a reduced matrix in case the target domain occupies a
larger geometric region than the origin domain, where the rows and
columns that correspond to dofs not taking part in the projection are
deleted.

to shearStress. Also in problem.hh computeBottomFrictionSource is
renamed to bottomFricitonSource.

For each element a object of a child class of FrictionLaw is
instantiated and stored within a vector.
This makes it possible to change the friction law on runtime, use also friction
laws which have more than one parameter, use spatial variying friction
values and even to use muliple friction laws.

The friction law compute now the bed shear stress instead of the source
term. So they return a quantity with a clear physical meaning, which can
be also used for other purpuses (e.g. sediment transport). Therefore the
computeSource method was renamed to computeShearStress.
computeShearStress uses now volvars instead of the explicit use of
waterDepth, u, v.