Documentation: write-out=table for v3 commands

Documentation/dev-guide/local_cluster.md

@@ -45,7 +45,7 @@ To interact with the started cluster by using etcdctl:
 # use API version 3
 $ export ETCDCTL_API=3
 
-$ etcdctl --endpoints=localhost:12379 member list
+$ etcdctl --write-out=table --endpoints=localhost:12379 member list
 +------------------+---------+--------+------------------------+------------------------+
 |        ID        | STATUS  |  NAME  |       PEER ADDRS       |      CLIENT ADDRS      |
 +------------------+---------+--------+------------------------+------------------------+

Documentation/op-guide/maintenance.md

@@ -66,7 +66,7 @@ $ while [ 1 ]; do dd if=/dev/urandom bs=1024 count=1024  | etcdctl put key  || b
 ...
 Error:  rpc error: code = 8 desc = etcdserver: mvcc: database space exceeded
 # confirm quota space is exceeded
-$ etcdctl endpoint status
+$ etcdctl --write-out=table endpoint status
 +----------------+------------------+-----------+---------+-----------+-----------+------------+
 |    ENDPOINT    |        ID        |  VERSION  | DB SIZE | IS LEADER | RAFT TERM | RAFT INDEX |
 +----------------+------------------+-----------+---------+-----------+-----------+------------+
@@ -105,7 +105,7 @@ A snapshot is taken with `etcdctl`:
 
 ```sh
 $ etcdctl snapshot save backup.db
-$ etcdctl snapshot status backup.db
+$ etcdctl --write-out=table snapshot status backup.db
 +----------+----------+------------+------------+
 |   HASH   | REVISION | TOTAL KEYS | TOTAL SIZE |
 +----------+----------+------------+------------+