Merge pull request #795 from FHenry/develop

htdocs/core/admin_extrafields.inc.php

htdocs/core/class/commonobject.class.php

htdocs/core/class/extrafields.class.php

htdocs/core/tpl/admin_extrafields_add.tpl.php

htdocs/core/tpl/admin_extrafields_edit.tpl.php

htdocs/install/mysql/migration/3.3.0-3.4.0.sql

htdocs/install/mysql/tables/llx_product_price.sql

htdocs/langs/ca_ES/admin.lang

htdocs/langs/en_US/admin.lang

htdocs/langs/en_US/errors.lang

htdocs/langs/es_ES/admin.lang

htdocs/langs/es_ES/errors.lang

htdocs/langs/fr_FR/admin.lang

htdocs/langs/fr_FR/errors.lang