[core.interfaces] bugfix
[core.cache] make attributes of Cachable private
[discretizations] provide methods for disabling logging
[tools.selfless] add selfless_arguments
[discretizations] use selfless_arguments for _with_arguments
[core.interfaces] make with_arguments an attribute
[discretizations] do not use dict_property

now unnecessary because of immutability
[core.interfaces] improve _with_via_init
[discretizations] simplify with_