Cleaning up unwanted files after updates
<updatecheck>
 - Cleaning Up After Updates
This feature can update an installed package to remove superfluous files after an installation.
Each pack can now specify an <updatecheck>
 tag that indicates which files are to be retained or deleted.
Includes and excludes can be defined as filesets, but no file name mappers can be used.
$INSTALL_PATH
 is treated as the base path for include/exclude patterns with relative paths.
Example:
<updatecheck> <include name="lib/**" /> <exclude name="config/local/**" /> </updatecheck>
This causes files in $INSTALL_PATH/lib
to be deleted and files in the $INSTALL_PATH/
config
sub-folder to be retained.
If no include or exclude pattern is given all files which were not part of the setup are deleted in $INSTALL_PATH
Be careful with this facility to not delete 3rd-party files coming from other installations, for instance plugins to a base application.
Example:
<updatecheck/>
This causes all files in $INSTALL_PATH
 that were not installed in the current installation to be deleted.