make polynomial degree a parameter
make suggestion for command line parameters
corrected small typo in output filename
make subsampling depth depend on polynomial degree
make coarse grid size a command line parameter
remove computation of pattern statistics
use BackendVectorSelector for pedagocial reasons.
One should be able to make a DOF vector without a grid operator.
move makeing of DOF vector up
use BackendVectorSelector
make adaptivity example work again