gear-menu: Re-add the organization settings link.

This re-adds the organization settings link and toggles the text
dependent on whether the user is an administrator or not.

Fixes: #4201.

static/js/admin.js

@@ -9,9 +9,9 @@ var all_streams = [];
 exports.show_or_hide_menu_item = function () {
     var item = $('.admin-menu-item').expectOne();
     if (page_params.is_admin) {
-        item.show();
+        item.find("span").text(i18n.t("Manage organization"));
     } else {
-        item.hide();
+        item.find("span").text(i18n.t("Organization settings"));
         $(".organization-box [data-name='organization-settings']")
             .find("input, button, select").attr("disabled", true);
     }

static/styles/zulip.css

@@ -2495,10 +2495,6 @@ button.topic_edit_cancel {
     text-decoration: line-through;
 }
 
-.admin-menu-item {
-    display: none;
-}
-
 /* embed */
 .message_content .message_embed {
     display: block;

templates/zerver/navbar.html

@@ -61,7 +61,8 @@
                   </li>
                   <li title="{{ _('Manage organization') }}" class="admin-menu-item">
                     <a href="#organization" role="button">
-                      <i class="icon-vector-bolt"></i> {{ _('Manage organization') }}
+                      <i class="icon-vector-bolt"></i>
+                      <span>{{ _('Manage organization') }}</span>
                     </a>
                   </li>
                   <li class="divider"></li>