You can uninstall or removes an installed libgammu-i18n package itself from Debian 8 (Jessie) through the terminal,
$ sudo apt-get remove libgammu-i18n
If you would like to remove libgammu-i18n and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove libgammu-i18n
If you use with purge options to libgammu-i18n package all the configuration and dependent packages will be removed.
$ sudo apt-get purge libgammu-i18n
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 libgammu-i18n