update readme

README.md

@@ -1,6 +1,6 @@
 <div align="center">
  
-   <img width="160" src="http://img.mamoe.net/2020/02/16/a759783b42f72.png" alt="logo">
+   <img width="160" src="http://img.mamoe.net/2020/02/16/a759783b42f72.png" alt="logo"></br>
    <img width="95" src="http://img.mamoe.net/2020/02/16/c4aece361224d.png" alt="logo">
     
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