Merge branch 'fix/remove-somerton-deprecations' into 'master'

dumux/porenetwork/2p/model.hh

dumux/porousmediumflow/2p/model.hh

dumux/porousmediumflow/2p1c/model.hh

dumux/porousmediumflow/2p2c/model.hh

dumux/porousmediumflow/2pnc/model.hh

dumux/porousmediumflow/2pncmin/model.hh

dumux/porousmediumflow/3p/model.hh

dumux/porousmediumflow/3p3c/model.hh

dumux/porousmediumflow/3pwateroil/model.hh

dumux/porousmediumflow/mpnc/model.hh

dumux/porousmediumflow/richards/model.hh

dumux/porousmediumflow/richardsextended/model.hh

...al/fluidmatrixinteractions/2p/test_thermalconductivity.cc