Add strings.

en.json

@@ -6,7 +6,8 @@
         "image_by": "Image by",
         "loading": "Loading…",
         "on": "On",
-        "off": "Off"
+        "off": "Off",
+        "disabled": "Disabled"
     },
     "login": {
         "title": "Login",
@@ -272,7 +273,8 @@
                 "overview": {
                     "title": "Overview",
                     "name": "Server Name",
-                    "description": "Channel Description"
+                    "description": "Channel Description",
+                    "system_messages": "System Message Channels"
                 },
                 "members": {
                     "title": "Members"