You can uninstall or removes an installed fgfs-models-base package itself from Debian 8 (Jessie) through the terminal,
$ sudo apt-get remove fgfs-models-base
If you would like to remove fgfs-models-base and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove fgfs-models-base
If you use with purge options to fgfs-models-base package all the configuration and dependent packages will be removed.
$ sudo apt-get purge fgfs-models-base
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 fgfs-models-base