Add request limiting by local port

[apatrida]

depends on #4, when we have multiple port listeners

We can therefore apply rate and request limiting on that port. For example, the cluster port should not be rate limited as a whole because internal cluster communication should be untouched. Another port could be added for the query load balancer and rate limited to protect the system, another port for updates (that do not use zkHost as locator, or another for just the admin UI. The default port is the Solr cluster communication port.