You can uninstall or removes an installed bareos-client package itself from Ubuntu 16.10 (Yakkety Yak) through the terminal,
$ sudo apt-get remove bareos-client
If you would like to remove bareos-client and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove bareos-client
If you use with purge options to bareos-client package all the configuration and dependent packages will be removed.
$ sudo apt-get purge bareos-client
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove bareos-client