Need for Porousmediumflow/Freeflow/Porenetwork type tag
Many properties that are grouped under
Implicit (especially many new ones on
next) are only useful for porousmediumflow problem. Further they are not restricted to an implicit time discretization. We should introduce a
Porousmediumflow Typetag that porousmedium flow models derive from. Many of the properties introduces for each sub model are actually also shared by all/most porousmediumflow models.
The same holds for freeflow / porenetwork / geomechanics.
Related to this: Some implicit properties might actually be independent of the time discretization as well and could be moved to the base properties.