Fix Markdown in table

Author: mmistakes

README.md

@@ -108,8 +108,7 @@ one of the following to your [`/_data/theme.yml`](_data/theme.yml) file:
 
 | `skin: sea` | `skin: soft` | `skin: steel` |
 | --- | --- | --- |
-| ![sea-skin](https://cloud.githubusercontent.com/assets/1376749/24115788/e27d818a-0d7a-11e7-8c56-2480e9ae83fb.png) | ![soft-skin](https://cloud.githubusercontent.com/assets/1376749/24115790/e6e548e8-0d7a-11e7-8e2d-d8053e8befd1.png)
- | ![steel-skin](https://cloud.githubusercontent.com/assets/1376749/24115799/eb2108e8-0d7a-11e7-8cc3-a6f22e4082ee.png) |
+| ![sea-skin](https://cloud.githubusercontent.com/assets/1376749/24115788/e27d818a-0d7a-11e7-8c56-2480e9ae83fb.png) | ![soft-skin](https://cloud.githubusercontent.com/assets/1376749/24115790/e6e548e8-0d7a-11e7-8e2d-d8053e8befd1.png) | ![steel-skin](https://cloud.githubusercontent.com/assets/1376749/24115799/eb2108e8-0d7a-11e7-8cc3-a6f22e4082ee.png) |
 
 ### Google Fonts