Fixes #4496: rudder-jetty package should conflict with standard jetty packages
Merge pull request #225 from jooooooon/bug_4496/trying_to_overwrite_etc_default_jetty_which_is_also_in_package_rudder_jetty_2_9_2_wheezy0

Fixes #4496: rudder-jetty package should conflict with standard jetty pa...