etcd: fix machines endpoint test
etcd: support v2 peers endpoint
etcd: support v2 store stats endpoint
etcd: separate raft and client port
etcd: support raft tls
etcd: support etcd server tls
etcd: support cors
main: generate 64bit id
raft: atomic load id
etcd: fix data race in transporter
raft: add atomicInt
raft: change index and term to int64
raft: change term to atomicInt
raft: add sm.Index
etcd: refactor tests
etcd: move util to test
server: remove unused file
v1: deprecate v1 support

Etcd moves to 0.5 without the support of v1.
v2: remove old tests
etcd: move server/usage.go to etcd/v2_usage.go