Update terminology XML and XSD files

There are some small issues that will have to be addressed: - terminology file does not have any `version` and last change `date` attributes - vocabulary names are translated in some languages, and they don't have any identifier -> suggest to add `openehr_id`, with an id infered from name - codesets and vocabulary should have a `status` attribute (trial, active, retired), considered to be `active` if missing - codes and rubric should have a `status` attribute (trial, active, retired), considered to be `active` if missing - add codeset/vocabulary `description` child node - add codeset/vocabulary `usage` child nodes, containing `url` and `name` - this will be filled in terminology usage by openEHR types - add codeset/vocabulary `reference` child nodes, containing `url` and `name` - this will be filled in external terminology references info