[Mailman-i18n] New translation: Slovak

[Martin Matuska]

Hi everybody,

I found out that Mailman does not support Slovak yet and have started
translating mailman to slovak a week ago. By today, I have translated
about 5000 lines (about 8000 still not translated) of mailman.po and did
not translate the templates yet. I use the czech translation (from SVN)
as a good starting point. I hope Slovak can be imported into future
releases of mailman.