Allow register records (ISO19135) to be converted to SKOS and used as thesauri in thesaurus keyword picker

[simonp]

ISO19135 register standard allows thesauri/codelists/controlled vocabs to be managed in GeoNetwork as metadata records (using iso19135 plugin schema already available).

Should be possible to add a thesaurus in SKOS format from an iso19135 catalog record to GeoNetwork by specifying uuid - do this by:

• adding a new type of thesaurus called 'register' which when activated creates a SKOS record from iso19135 and inserts into GeoNetwork ThesaurusManager?
• ThesaurusManager? checks and updates SKOS if iso19135 metadata record changes
• encode iso19135 to SKOS XSLT
• do not allow user to update register type of thesaurus in GeoNetwork thesaurus panel - this should be done by modifying the base iso19135 record instead using the GeoNetwork editor etc - ThesaurusManager? will detect that iso19135 record has changed and will recreate SKOS for GeoNetwork thesaurus

Two sample iso19135 records (one for ANZLIC theme keywords and the other for NASA GCMD science/theme keywords) have been created to test this function and are available in the iso19135 plugin schema

[simonp]

Added in svn rev 8921