Math: add a function for linear regression

See merge request !2569

[pnm] Various imrprovements

See merge request !2568

* function doesn't add any value
* use ctor of BasicParams directly

Extend intersection tests for 1d3d

Closes #987

See merge request !2453

[variablesbackend] Generalize vector dofbackend

Closes #1014

See merge request !2564

[fixup][md] Fix parallel check in multidomain assembler

See merge request !2562

Remove general outflow bc type

Closes #972

See merge request !2552

[cleanup] Delete installdumux.sh

See merge request !2560

has been replaced by the Python script installdumux.py

[doc][doxygen] Reduce error log to what we had for release 3.3.

See merge request !2558

[test] Add test with nonoverlapping grid manager that cannot communicate

See merge request !2557

Fix richards local res

See merge request !2559

[doc][handbook] Change package name scrpage2 to newer version scrlayer-scrpage.

See merge request !2556

gasViscosisty-update-in-changelog

Closes #1007

See merge request !2554

Addresses issue #1007

[newton] Set default parameters directly

Closes #1003

See merge request !2551

Feature/water vapor viscosity

Closes #573

See merge request !2452

Gabi Seitz authored 4 years ago and Timo Koch committed 3 years ago

with contributions of Holger and Bernd

The following test results had to be adapted:
test_md_boundary_darcy2p2c_stokes1p2c_horizontal
test_md_boundary_darcy2p2cni_stokes1p2cni_horizontal
test_2p1cni_steaminjection_waterwet_box
test_2p1cni_steaminjection_waterwet_tpfa
test_2p2cni_waterair_box
test_2p2cni_waterair_buoyancy_box
test_dec2p2c
test_multiphysics2p2c
test_1pncmin_box
test_3p3cni_kuevette_box
test_3p3cni_kuevette_tpfa
test_3pwateroil_sagd_box