update readme

Author: ScullWM

readme.md

@@ -2,6 +2,8 @@
 
 Without creating an account (just giving an email and a passphrase to generate your custom hashkey), upload instantly your screenshot and paste direct url to it without any limitation.
 
-![](http://www.updemia.com/static/e/c/xl/58d41fc47ffdf.png)
+<p align="center"><a href="https://github.com/updemia/client-macos" target="_blank">
+    <img src="http://www.updemia.com/static/e/d/xl/58f74e218f7ac.png">
+</a></p>
 
 Screenshots are uploaded on www.updemia.com