Update doc of listen-client-urls and listen-client-http-urls

Signed-off-by: Sadamingh <yxing11@usfca.edu>

content/en/docs/v3.4/op-guide/configuration.md

@@ -65,12 +65,20 @@ The list of flags provided below may not be up-to-date due to ongoing developmen
 + invalid example: "http://example.com:2380" (domain name is invalid for binding)
 
 ### --listen-client-urls
-+ List of URLs to listen on for client traffic. This flag tells the etcd to accept incoming requests from the clients on the specified scheme://IP:port combinations. Scheme can be either http or https. Alternatively, use `unix://<file-path>` or `unixs://<file-path>` for unix sockets. If 0.0.0.0 is specified as the IP, etcd listens to the given port on all interfaces. If an IP address is given as well as a port, etcd will listen on the given port and interface. Multiple URLs may be used to specify a number of addresses and ports to listen on. The etcd will respond to requests from any of the listed addresses and ports.
++ List of URLs to listen on for client traffic. This flag tells the etcd to accept incoming requests from the clients on the specified scheme://IP:port combinations as long as --listen-client-http-urls is not specified. Scheme can be either http or https. Alternatively, use `unix://<file-path>` or `unixs://<file-path>` for unix sockets. If 0.0.0.0 is specified as the IP, etcd listens to the given port on all interfaces. If an IP address is given as well as a port, etcd will listen on the given port and interface. Multiple URLs may be used to specify a number of addresses and ports to listen on. The etcd will respond to requests from any of the listed addresses and ports.
 + default: "http://localhost:2379"
 + env variable: ETCD_LISTEN_CLIENT_URLS
 + example: "http://10.0.0.1:2379"
 + invalid example: "http://example.com:2379" (domain name is invalid for binding)
 
+### --listen-client-http-urls
++ List of URLs to listen on for HTTP-only client traffic. This flag tells the etcd to accept incoming requests from clients on the specified http://IP:port combinations. Enabling this flag removes HTTP services from --listen-client-urls. Use this flag when you want to segregate HTTP traffic from other protocols. If 0.0.0.0 is specified as the IP, etcd listens to the given port on all interfaces. If an IP address is given as well as a port, etcd will listen on the given port and interface. Multiple URLs may be used to specify a number of addresses and ports to listen on. The etcd will respond to requests from any of the listed addresses and ports.
++ default: ""
++ env variable: ETCD_LISTEN_CLIENT_HTTP_URLS
++ example: "http://10.0.0.1:2383"
++ invalid example: "http://example.com:2383" (domain name is invalid for binding)
+
+
 ### --max-snapshots
 + Maximum number of snapshot files to retain (0 is unlimited)
 + default: 5

content/en/docs/v3.5/op-guide/configuration.md

@@ -53,7 +53,9 @@ The list of flags provided below may not be up-to-date due to ongoing developmen
 --listen-peer-urls 'http://localhost:2380'
   List of URLs to listen on for peer traffic.
 --listen-client-urls 'http://localhost:2379'
-  List of URLs to listen on for client traffic.
+  List of URLs to listen on for client grpc traffic and http as long as --listen-client-http-urls is not specified.
+--listen-client-http-urls ''
+  List of URLs to listen on for http only client traffic. Enabling this flag removes http services from --listen-client-urls.
 --max-snapshots '5'
   Maximum number of snapshot files to retain (0 is unlimited).
 --max-wals '5'

content/en/docs/v3.6/op-guide/configuration.md

@@ -53,7 +53,9 @@ The list of flags provided below may not be up-to-date due to ongoing developmen
 --listen-peer-urls 'http://localhost:2380'
   List of URLs to listen on for peer traffic.
 --listen-client-urls 'http://localhost:2379'
-  List of URLs to listen on for client traffic.
+  List of URLs to listen on for client grpc traffic and http as long as --listen-client-http-urls is not specified.
+--listen-client-http-urls ''
+  List of URLs to listen on for http only client traffic. Enabling this flag removes http services from --listen-client-urls.
 --max-snapshots '5'
   Maximum number of snapshot files to retain (0 is unlimited).
 --max-wals '5'