Update laravel.md

In order to get Laravel generating proper URLs, the TrustProxies middleware needs to be changed.

docs/frameworks/laravel.md

@@ -141,6 +141,19 @@ uploading your assets to S3 automatically.
 For more details, see the [Websites section](/docs/websites.md) of this documentation
 and the official <a href="https://github.com/getlift/lift/blob/master/docs/server-side-website.md">Lift documentation</a>.
 
+### Trusted proxies
+
+Because Laravel is executed through API Gateway, the Host header is set to the API Gateway host name.  Helper functions 
+such as redirect() will incorrectly use this host name.  The correct host name is set on X_FORWARDED_HOST.
+
+To get Laravel to use X_FORWARDED_HOST instead, edit the TrustProxies middleware and set $proxies to the * wildcard:
+
+``` class TrustProxies extends Middleware
+{
+...
+    protected $proxies = '*';
+```
+
 ### Assets in templates
 
 Assets referenced in templates should be via the `asset()` helper: