Is there an option to delete the rules / pojo / package / anything that we import or create in drools guvnor ?
Guvnor version is 5.5.0 Deployed on Tomcat 7.0.21
I don't have a running installation of that version of Guvnor at the moment, so the following is based on memory. Hopefully it's close to what you need.
If you access the package screen, one of the drop-down menus has an "archive" option. Archive anything you wish to delete.
However, when you archive a resource, it is not deleted. To properly delete your archived rules and packages, go to the admin screen, where there is a link which lets you view your archived items:
http://docs.jboss.org/drools/release/5.5.0.Final/drools-guvnor-docs/html_single/#d0e3275
You can then select a package and click "Permanently delete package". Alternatively, tick the check-box against any archived items you are ready to delete permanently and click "Delete selected asset".