Added nl_NL in UTF8

htdocs/langs/en_US/admin.lang

htdocs/langs/en_US/agenda.lang

htdocs/langs/en_US/banks.lang

htdocs/langs/en_US/bills.lang

htdocs/langs/en_US/boxes.lang

htdocs/langs/en_US/categories.lang

htdocs/langs/en_US/commercial.lang

htdocs/langs/en_US/companies.lang

htdocs/langs/en_US/compta.lang

htdocs/langs/en_US/contracts.lang

htdocs/langs/en_US/deliveries.lang

htdocs/langs/en_US/dict.lang

htdocs/langs/en_US/domains.lang

htdocs/langs/en_US/donations.lang

htdocs/langs/en_US/ecm.lang

htdocs/langs/en_US/errors.lang

htdocs/langs/en_US/exports.lang

htdocs/langs/en_US/interventions.lang

htdocs/langs/en_US/ldap.lang

htdocs/langs/en_US/mails.lang