Put logic into gallery.panel.js so that when the panel is submitted, the submit button is disabled and the user is no longer able to submit multiple clicks.

lib/gallery.panel.js

@@ -50,6 +50,12 @@
        var self = this;
        $("#g-panel td form").ajaxForm({
          dataType: "json",
+         beforeSubmit: function(formData, form, options) {
+           form.find(":submit")
+             .addClass("ui-state-disabled")
+             .attr("disabled", "disabled");
+           return true;
+         },
          success: function(data) {
            if (data.form) {
              $("#g-panel td form").replaceWith(data.form);