Add a reference to an object type to validate

Known as referenced standard, it is used to determine which kinds of objects can be validated using the EVSClient. 

The "add a reference standard" feature allows the tool administrator to create a new content type to be offered for validation to the end user.

A Reference standard has

• a name, refers to the standard or IHE profile (HL7v2, ATNA, XML ...),
• a label,
• a version,
• a validator filter (used as discriminator to display only the validators of interest in a given context, eg. Swiss EPR),
• a link to the XSL stylesheet to use to display the content of the object beeing validated

A reference standard cannot be removed except by executing a SQL query directly in the database.