Get IP for hosts from etcd rather than just using hostname
Get IP for hosts from etcd rather than just using hostname


Former-commit-id: 18bc636e336294d603b96771b7a49b8db96d2e68
projectcalico/libcalico,tomdee/libcalico,caseydavenport/libcalico,L-MA/libcalico,TrimBiggs/libnetwork-plugin,tomdee/libnetwork-plugin,robbrockbank/libcalico,insequent/libcalico,TrimBiggs/libcalico,djosborne/libcalico,projectcalico/libnetwork-plugin,Symmetric/libcalico,TrimBiggs/libnetwork-plugin,alexhersh/libcalico,plwhite/libcalico