Remove settings which are in Doxystyle anyway
Use path references from the root of the project

This means that it becomes harder to move this directory around, but
that gain is relatively small anyway. It is however necessary to do
this if we are not going to do a recursive build style.
Move tests out of source tree
Remove dead directory references
Import cmake/ from commit 5f82198c in opm-core
Remove opm-core specific customizations
Search and replace opm-core with dune-cornerpoint

Add dependencies that are specific for this library as well as doing
the textual replacement in the configuration file.
Ignore output from CMake build
Remove remnants of the Autotools build system