DLF,  11th April 2006   Slide 21
Response Format Additions
* Allow record Identifier (metadata level) to be returned in the
  record structure
* Allow the full base URL to be returned in the response
(within echoedRequest)
<record>
  <recordSchema>info:srw/schema/1/dc-v1.1</recordSchema>
  <recordPacking>xml</recordPacking>
  <recordIdentifier>info:pmid/15411833</recordIdentifier>
  <recordData> ... </recordData>
</record>
<echoedRequest>
  <baseUrl>http://srw.cheshire3.org/services/spy</baseUrl>
  <version>1.2</version>
  ...
</echoedRequest>