Converts the xml representation of a
DcsDeliverableUnit to the Java object model and back.
Example XML:
<DeliverableUnit id="urn:sdss:12345">
<!-- The collection exists, and this is its DCS identifier -->
<collection ref="http://dataconservancy.org/collections/SDSS_run_5" />
<title>SDSS file 12345</title>
<creator>Astrophysical Research Consortium (ARC)</creator>
<subject>Astronomy</subject>
<formerExternalRef>http://das.sdss.org/blahblahblah...</formerExternalRef>
<!-- An example of metadata inline -->
<metadata schemaURI="http://sdss.org/metadata/astroSchema.example.xsd">
<md xmlns:astro="http://sdss.org/astro">
<astro:skyCoverage>all of it</astro:skyCoverage>
<astro:enfOfWorldFactor>-1</astro:enfOfWorldFactor>
</md>
</metadata>
<!--
An example of metadata that exists as a file, in this case it is
submitted in the SIP
-->
<metadata ref="urn:sdss:12345/metadata" />
</DeliverableUnit>