Add CMake detection by copying
opm-common/cmake/Modules at https://github.com/OPM/opm-common/,
Remove hack for GCC <= 4.6. Add Dune's IsNumber specialization.
Test by using
Scalar and recalculating the one-phase
incompressible TPFA test with analytic Jacobian.
A quite annoying detail is that
dumux/common/quad.hh has to be included
before any other Dune module, at least I couldn't find a better way.