Refactored DB Forge

- PDO subdrivers are isolated from each other now.
- Added compatibility for pretty much all of the features, for every DB platform.
- Unified the way that stuff works in general.
- Fixes issue #1005.
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index cbc6295..717d7f6 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -154,6 +154,8 @@
    -  Added MySQL client compression support.
    -  Added encrypted connections support (for *mysql*, *sqlsrv* and PDO with *sqlsrv*).
    -  Removed :doc:`Loader Class <libraries/loader>` from Database error tracing to better find the likely culprit.
+   -  Added an optional second parameter to ``drop_table()`` in :doc:`Database Forge <database/forge>` that allows adding the IF EXISTS condition.
+   -  Removed the optional AFTER clause from :doc:`Database Forge <database/forge>` method ``add_column()``.
 
 -  Libraries