everywhere: add option to export data

frontend/js/dashboard-export.js

@@ -0,0 +1,26 @@
+(function (global, document) {
+  "use strict";
+
+  (document);
+
+  global.domainExportBegin = function() {
+    var data = global.dashboard.$data;
+
+    var json = {
+      "ownerToken": global.cookieGet("commentoOwnerToken"),
+      "domain": data.domains[data.cd].domain,
+    }
+
+    global.buttonDisable("#domain-export-button");
+    global.post(global.origin + "/api/domain/export/begin", json, function(resp) {
+      global.buttonEnable("#domain-export-button");
+      if (!resp.success) {
+        global.globalErrorShow(resp.message);
+        return;
+      }
+
+      global.globalOKShow("Data export operation has been successfully queued. You will receive an email.");
+    });
+  };
+
+} (window.commento, document));