Add common themes

Home.md

@@ -12,6 +12,7 @@ Welcome to the Ombi wiki! Please note the wiki is maintained by TidusJar and the
 * [All the *Arrs (Sonarr etc)](https://github.com/tidusjar/Ombi/wiki/Arr-Settings)<br>
 * [Authentication](https://github.com/tidusjar/Ombi/wiki/Authentication-Settings)<br> 
 * [Customization](https://github.com/tidusjar/Ombi/wiki/Customization-Settings)<br>
+    * [Common Themes](https://github.com/tidusjar/Ombi/wiki/Ombi-v4-Custom-Themes)
 * [DogNzb](https://github.com/tidusjar/Ombi/wiki/DogNzb-Settings)<br>
 * [Issues](https://github.com/tidusjar/Ombi/wiki/Issue-Settings)<br> 
 * [Jobs/Tasks/Schedules](https://github.com/tidusjar/Ombi/wiki/Jobs-Tasks-Schedules)<br>