[Major revision] Update attributes available for <image>

[kerstarno]

Provide a general summary of the issue in the Title above. Delete the part of the issue template that does not apply depending on whether you describe a change to an existing element / attribute or the addition of a new one.

Creator of issue

State your name, organisation and ways to reach you. Name: Kerstin Arnold Organisation: Archives Portal Europe Foundation, Working Group on Standards Email: standards@archivesportaleurope.net GitHub username (if applicable): @kerstarno

Changes to existing element / attribute

Give the current name of the element / attribute. Include the tag name and the full name. Name: <image>

Change in content model (elements)

List all sub-elements and attributes that should be removed from or added to the element's content model.

• Make @href optional
• Add the optional attributes @audience with values "external", "internal" (0), @id (0), @target (0); @conventionDeclarationReference (0), @maintenanceEventReference (0), @sourceReference (0); @linkRole (0); @localTypeDeclarationReference; option to include attributes from any other namespace

[kerstarno]

No conversion change required as <image> remains optional and repeatable within <repository> and <repositories> and already includes the attribute @href, @linkTitle and @localType, which will be available as such in EAG 3.0 as well (see also #4).