po: update po/el/contribute.po (pulled from Transifex.net by CiviCRM l10n maintainer)
po: update po/el/event.po (pulled from Transifex.net by CiviCRM l10n maintainer)
po: update po/el.po (pulled from Transifex.net by CiviCRM l10n maintainer)
po: update po/pt_BR.po (pulled from Transifex.net by CiviCRM l10n maintainer)