Fix rendering of logo in README

Author: tuxu

README.md

@@ -1,6 +1,6 @@
 # Jupyter Notebook Viewer
 
-![Icon](Jupyter Notebook Viewer/Images.xcassets/AppIcon.appiconset/icon_256x256.png)
+![Icon](Jupyter%20Notebook%20Viewer/Images.xcassets/AppIcon.appiconset/icon_256x256.png)
 
 A native macOS application to view
 [Jupyter](https://jupyter.org/)/[IPython](https://ipython.org/) notebooks.
@@ -32,4 +32,4 @@ A native macOS application to view
 This project is licensed under the MIT license. See [LICENSE.md](LICENSE.md) for
 details.
 
-© 2017 [Tino Wagner](http://www.tinowagner.com/)
+© 2017 [Tino Wagner](http://www.tinowagner.com/)