Fix/missing includes

See merge request !2486

Fix/various small

See merge request !2485

Installdumux.py with dumux and dune versions as a command-line options

Closes #992

See merge request !2481

[shallowwater][diffusion] add turbulent diffusion to shallow water

Closes #706

See merge request !2243

[pnm] Improve grid generation

See merge request !2483

assemble matrix only once in the linear pde solver

See merge request !2239

Bernd Flemisch authored 4 years ago and Timo Koch committed 4 years ago

So far, the `LinearPDESolver` (re)assembles the matrix in its
`solve` function unconditionally. This might be unnecessary if the
matrix did not change compared to the previous call to `solve`.
Make a first attempt to avoid the unnecessary calculation by
adding a corresponding control flag.

Feature/box scvf num outside scvs

See merge request !2469

Fix/pnm gridgeo

See merge request !2482