Increase batch delay on IpsetManager.
Increase batch delay on IpsetManager.

This improves performance under heavy churn.

Metaswitch/calico,neiljerram/felix,TrimBiggs/calico,TrimBiggs/calico,matthewdupre/felix,neiljerram/felix,neiljerram/felix,neiljerram/felix,matthewdupre/felix,Metaswitch/calico