添加邮箱功能

src/views/register.vue

@@ -90,7 +90,7 @@ export default {
       },
       registerRules: {
         username: [
-          {required: true, trigger: "blur", message: "请输入您的账号"},
+          {required: true, trigger: "blur", message: "请输入您的账号/邮箱"},
           {min: 2, max: 20, message: '用户账号长度必须介于 2 和 20 之间', trigger: 'blur'}
         ],
         password: [