Remove all IPs

[djahandarie]

I think it'd be a nice API improvement (both ergonomically and efficiency-wise) if you could remove all the IPs in one go, for cases where you want to load in a new set of IPs.

(Alternatively a shutdown method would work as well, but in #25 you seem to argue against that architecture.)

[bparli]

Hey @djahandarie I'm open to a remove_all_ipaddrs method if its helpful. Alternatively, I'm wondering if an add_batch_ipaddr and remove_batch_ipaddr (where both take an array of &str) might be more useful?

#25 isn't about a shutdown method per se (at least my reading of it). I'm not against an explicit shutdown if its useful, just didn't think it would be.