This commit affects all properties and member variables

This commit affects all properties and member variables

[handbook] delete old tutorial

See merge request !671

Cleanup/volvars

See merge request !670

* use correct class name

[2p1c] Port 2p1cni model to next

See merge request !522

Kilian Weishaupt authored 7 years ago and Timo Koch committed 7 years ago

* the test failed compared to the ref solution generated on the old
  master
* the reason for this is the change of how rho in context of gravity
  is calculated

* using rho = 0.5*(elemVolVars[scvf.insideScvIdx()].density(phaseIdx)
            + elemVolVars[scvf.outsideScvIdx()].density(phaseIdx));

  instead of interpolating the value of rho onto the face made the test
  pass w.r.t the the old solution

* we prefer interpolationg rho, however, therefore the ref solution is
  updated
* using the interpolated rho also decreases the number of timesteps from 8 to 7
  (compared to the old master)