Update CHANGELOG.md

Author: barryvdh

CHANGELOG.md

@@ -8,6 +8,10 @@ All notable changes to this project will be documented in this file.
 ### Fixed
 
 ### Changed
+- Use of doctrine/dbal [#1512 / barryvdh](https://github.com/barryvdh/laravel-ide-helper/pull/1512) 
+  With this functionality gone, a few changes have been made:
+- support for custom datatypes has been dropped (config `custom_db_types`) unknown data types default to `string` now and to fix the type, add a proper cast in Eloquent
+- You _might_ have top-level dependency on doctrine/dbal. This may have been in the past due to ide-helper, we suggest to check if you still need it and remove it otherwise
 
 ### Added