Resolve calling .list without pagination bottlenecks

* ensure pagination is used in all table views (we will have to enhance filtering in ironic, nova, etc..)

* for overview pages statistics (all statistics that are using .list() without pagination), we have 2 options:
** statistics will be stored in Ceilometer, it would have to be data from notifications, so we don't have obsolete data. We will need to enhance Ceilometer stats a bit maybe.
** ironic, nova, etc. will support API for basic statistics we are using