Update etcd.go

etcdmain: Fix misuse "-addr" flag

In code, it uses "-advertise-client-urls" or "-addr" flags to get the list of this member's peer URLs, 
It should be using "-peer-addr" flag instead of "-addr" flag.
etcdserver: close idle connections when stop sendhub
wal: not return ErrIndexNotFound in ReadAll

This IndexNotFound case is reasonable now because we don't write dummy
entries into wals any more.
doc: uses spaces consistently in sample JSON

Replaces spurious uses of tabs with four spaces.  Removes strange
unicode space character with standard space character.
build: statically compile etcdctl binary
Merge pull request #1827 from lamielle/doc-whitespaces

doc: uses spaces consistently in sample JSON
raft: logging state change events and events on bad path
Merge pull request #1823 from xiang90/raft_log

raft: logging state change events and events on bad path
Merge pull request #1824 from yichengq/241

etcdserver: close idle connections when stop sendhub
raft: use index in entry
Merge pull request #1829 from xiang90/raft_index

raft: use index in entry
raft: log snapshot events
Merge pull request #1830 from xiang90/raft_snap_log

raft: log snapshot events
raft: move good case of truncateAndAppend to the first place
raft: not call stableTo for restored snapshot

Stable has been set when restoring the snapshot in raftlog, so we don't need
to set it after advance.
Merge pull request #1833 from yichengq/244

raft: not call stableTo for restored snapshot
raft: clearify that the firstIndex might not be available.
Merge pull request #1831 from xiang90/fix_unstable

raft: fix unstable
raft: panic on bad slice
Merge pull request #1836 from xiang90/panic_slice

raft: panic on bad slice