updating change log.

laravel/documentation/changes.md

@@ -37,6 +37,7 @@
 - Fix issue with eager loading and `first` or `find`.
 - Fix bug causing parameters to not be passed to `IoC::resolve`.
 - Allow the specification of hostnames in environment setup.
+- Added `DB::last_query` method.
 
 <a name="upgrade-3.2.2"></a>
 ## Upgrading From 3.2.1