Add link target verbage

Service-Widgets.md

@@ -4,6 +4,8 @@ Unless otherwise noted, URLs should not end with a `/` or other API path.  Each
 
 Each service can have one widget attached to it (often matching the service type, but thats not forced).
 
+In addition to the href of the service, you can also specify the target location in which to open that link.  See [Link Target](https://github.com/benphelps/homepage/wiki/Settings#link-target) for more details.
+
 Using Emby as an example, this is how you would attach the Emby service widget.
 
 ```yaml