修改了重复密码验证的js，精简代码量，减少了重复的校验，减少了valuedator中confirm的参数 [ci skip]

static/src/js/lib/formValidation/validator/usernameCheck.js

@@ -1,7 +1,6 @@
 /**
  * usernameCheck validator
  */
-
 (function(root, factory) {
 
     "use strict";
@@ -13,7 +12,6 @@
         // planted over the root!
         factory(root.jQuery, root.FormValidation);
     }
-
 }(this, function ($, FormValidation, csrfHeader) {
     FormValidation.I18n = $.extend(true, FormValidation.I18n || {}, {
         'en_US': {
@@ -22,23 +20,18 @@
             }
         }
     });
-
     FormValidation.Validator.usernameCheck = {
-
         validate: function(validator, $field, options) {
                     if ($field.val() == '')
                         return true;
                     return !$.ajax({
-                    async: false,
-                    beforeSend: csrfHeader,
-                    url: "/api/username_check/",
-                    data: {username: $field.val()},
-                    dataType: "json",
-                    method: "post",
-
-
-            }).responseJSON.data;
-
+                        async: false,
+                        beforeSend: csrfHeader,
+                        url: "/api/username_check/",
+                        data: {username: $field.val()},
+                        dataType: "json",
+                        method: "post",
+                    }).responseJSON.data;
         }
     };
 }));