Merge branch 'fix/remove-phase-idx' into 'master'

dumux/common/properties.hh

dumux/freeflow/compositional/kepsilonncmodel.hh

dumux/freeflow/compositional/komegancmodel.hh

dumux/freeflow/compositional/lowrekepsilonncmodel.hh

dumux/freeflow/compositional/navierstokesncmodel.hh

dumux/freeflow/compositional/oneeqncmodel.hh

dumux/freeflow/compositional/zeroeqncmodel.hh

dumux/freeflow/navierstokes/model.hh

dumux/freeflow/properties.hh

dumux/freeflow/rans/oneeq/model.hh

dumux/freeflow/rans/twoeq/kepsilon/model.hh

dumux/freeflow/rans/twoeq/komega/model.hh

dumux/freeflow/rans/twoeq/lowrekepsilon/model.hh

dumux/freeflow/rans/zeroeq/model.hh

dumux/porousmediumflow/1pncmin/model.hh

dumux/porousmediumflow/richardsnc/model.hh

test/freeflow/navierstokesnc/channeltestproblem.hh

test/freeflow/navierstokesnc/densityflowproblem.hh

test/freeflow/navierstokesnc/msfreeflowtestproblem.hh

test/freeflow/rans/pipelauferproblem.hh