esp_websocket_client: Add websocket client component

Closes https://github.com/espressif/esp-idf/issues/2829

examples/protocols/websocket/main/Kconfig.projbuild

@@ -0,0 +1,9 @@
+menu "Example Configuration"
+
+    config WEBSOCKET_URI
+        string "Websocket endpoint URI"
+        default "ws://echo.websocket.org";
+        help
+            URL of websocket endpoint this example connects to and sends echo
+
+endmenu