Updated Slovenian translation.

* po/sl.po: Updated Slovenian translation from the Translation
Project.
Updated various translations from the Translation Project.

* po/ru.po: Updated Russian translation from the Translation
Project.
* po/fr.po: Updated French translation.
* po/pt_BR.po: Updated Brazilian Portuguese translation.
* po/it.po: Updated Italian translation.
* po/sr.po: Updated Serbian translation.
* po/eo.po: Updated Esperanto translation.
* po/tr.po: Updated Turkish translation.
* po/fi.po: Updated Finnish translation.
* po/el.po: Updated Greek translation.
find/find.1: Fix highlighting