Adding a new test problem for the mpnc model:

Local chemical equilibrium and local thermal non-equilibrium with two energy equations. 

A new fluidsystem with constant properties is implemented. 

The fluid temperature on the right boundary is verified by an analytical approximation for the stationary configuration.

reviewed by Christoph

git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@12743 2fb0f335-1f38-0410-981e-8018bf24f1b0