Forgotten file from 61c41a153e6bc5968de8f1bd109b4f68dec070dd

File is a cmake script to discover where to install python packages.
It also defines an install_python function to install stuff in that directory.
:bug: incorrect variable name in lookup recipe

Dune required when Dune_FIND_REQUIRED is set. Dune_REQUIRED comes from parsing the lookup macro.
Dune's find and lookup hardened in CMake

- Patches are in a cmake directory
- Sub-modules only depend on the submodules they do require. Better for parallel builds.
- :bug: FindDune used to fail when called without REQUIRED and when a component was not found.
  Now, a component can be required before Dune_FOUND is set to true, and yet the call not fail if
  Dune itself it not required.
- foamgrid installs a  pkg-config files, so it can be found the same way the other submodules are.
Allows for ALUGrid. Does not compile with ALUGrid.

Adds a lookup recipe for ALUGrid, and modifies the Dune lookup recipe to use ALUGrid.
However, there seems to be a missing ``globalBarycentricRefine`` member function in BEM, so that it
is not yet possible to compile BEM with ALUGrid.
Uses CBlas rather BLAS find-module cmake recipe
Remove AHMED from available options
:lipstick: remove some extra whitespaces
Have Trilinos install headers in sub-dir

Used to have everything installed right under include, but that's a bit messy.