added '%' to forbiddenPages

lib/models/page.js

@@ -410,7 +410,7 @@ module.exports = function(crowi) {
 
   pageSchema.statics.isCreatableName = function(name) {
     var forbiddenPages = [
-      /\^|\$|\*|\+|#/,
+      /\^|\$|\*|\+|#|%/,
       /^\/-\/.*/,
       /^\/_r\/.*/,
       /^\/_apix?(\/.*)?/,