新增客户，新增第一个联系人，默认选择默认用户“是”

http://zentao.jdshangmen.com/bug-view-12.html

src/views/ecw/customer/edit.vue

@@ -592,7 +592,7 @@ export default {
         // "customerId": 0,
         "department": "",
         "email": "",
-        "isDefault": undefined,
+        "isDefault": this.form.customerContacts.length === 0 ? 1 : 0,
         "name": "",
         "phoneNew": "",
         "position": "",