fix：限制名字15个

pages/user/user.wxml

@@ -11,7 +11,7 @@
     <view class="item">
       <text>用户昵称</text>
       <view class="ir">
-        <input value="{{nickname}}" class="ipname" bindinput="updateNickName"></input>
+        <input maxlength="15" value="{{nickname}}" class="ipname" bindinput="updateNickName"></input>
       </view>
     </view>
     <view class="item">