Revert "[cmake.cmake_config.h] make more sense"

This reverts commit 505c6fbf9ecabbef3e116202703bed15502e71fd.

Did not work, still needs improvement overall!
[cmake.cmake_config.h]
[common.math] make the test compile
[common.math] whitespace changes
(had to wait for the compile)
[fem.namespace] actually define them to one
[function.interface] let them all default to rangeDimCols = 1
[test.fem_projection] added missing evaluate
[test.function] make compile again
[test.grid_provider] make compile again
[test.la_solver] make compile again
is  only for sparse atm, should be for dense at some point
[test.localfunction] make compile again
added handling of Dune::Fem namespace for dune-multiscale