Convert ETCD_AUTHORITY to environment variable
Convert ETCD_AUTHORITY to environment variable


Former-commit-id: 31fb0c118e0eb9c0987e9d0e7f45c4de457d43b6
insequent/libcalico,djosborne/libcalico,robbrockbank/libcalico,TrimBiggs/libcalico,L-MA/libcalico,TrimBiggs/libnetwork-plugin,caseydavenport/libcalico,tomdee/libnetwork-plugin,projectcalico/libnetwork-plugin,Symmetric/libcalico,alexhersh/libcalico,TrimBiggs/libnetwork-plugin,plwhite/libcalico,tomdee/libcalico,projectcalico/libcalico