Add a AuPager component

[Windvis]

Most of our applications use the au-data-table-number-pagination component if they need a pagination feature outside of the AuDataTable .

This works, but that component is an implementation detail that leaked into the public because of the way Ember traditionally worked. This limits our refactoring options.

Webuniversum also has a Pager component which we can implement here as well. We can then deprecate using the AuDataTableNumberPagination component directly and guide users to the AuPager component instead.

The Webuniversum documentation is no longer online, but we can use these docs as a reference in the meanwhile.