[container.interfaces] some clean up
* use DUNE_PYMOR_SSIZE_T, refs #8
* remove exception specifiers, refs #4
[la.container] use DUNE_PYMOR_SSIZE_T
* refs #8
[la.container.dunedynamic] use correct type
[la.container.dunedynamic] minor clean up
* use DUNE_PYMOR_SSIZE_T, refs #8
* remove exception specifiers, refs #4
[la.container.eigen] fixed wrong type
[la..container.eigen] minor clean up
* use DUNE_PYMOR_SSIZE_T, refs #8
* remove exception specifiers, refs #4