Statistics: Add basic pagination to listeners
Statistics: Add basic pagination to listeners

The listeners table now show up to 20 listeners by default. I've added
a basic pagination system with two buttons: one to show 20 more, the
other to show all listeners at once.

This does not mean that the "fetch listener" API calls are paginated;
the listener list is fetched at once without any pagination. The
pagination is client-side only for now, until Cast has support for
paginated API calls.

Innovate-Technologies/control,Innovate-Technologies/control,Innovate-Technologies/control