Fix/cc ghost assembly

Closes #817

See merge request !1862

[cleanup] Delete deprecated basefvgridgeometry.hh

See merge request !1856

[freeflow][test] Remove unnecessary function sourceAtPos set to zero (is the default anyway).

See merge request !1847

Freeflow/tests tidy eps

See merge request !1859

Delete stamp-vc

See merge request !1857

[cleanup] Use if constexpr to replace SFINAE

See merge request !1858

[test][material][components] added new components needed for the biomin example

See merge request !1855

There seems to be no point in having this. It's pretty easy to find out if you have a git repository or a tarball

[darcystokes] Remove velocity output from reference solution

See merge request !1853

[test][darcystokes] Disable velocity output

See merge request !1852

The velocity output (post-processing)
is not very exact and makes it hard to compare
the results to a reference solution.

Fix/test 2ptracer vangenuchten

See merge request !1851

[vangenuchten] Introduce pore-connectivity parameter L

See merge request !1807

Gabi Seitz authored Jan 29, 2020 and Timo Koch committed Jan 31, 2020

cornerpoint test is missing

* Use l in krw/krn instead of hard-coded l=0.5
* Correct the non-wetting relperm to comply with the Mualem model
* Correct the non-wetting relperm derivative