add field to reference data usage citations

[mbjones]

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Author Name: Matt Jones (Matt Jones)
Original Redmine Issue: 6283, https://projects.ecoinformatics.org/ecoinfo/issues/6283
Original Date: 2013-12-06
Original Assignee: Matt Jones

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Consider adding an optional top level field to eml-dataset to provide this, possibly something like:

@/eml/dataset/dataUsageCitation which would be of type CitationType
@

See discussion on eml-dev regarding this issue:
http://lists.nceas.ucsb.edu/ecoinformatics/pipermail/eml-dev/2013-December/002004.html

[mbjones]

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Original Redmine Comment
Author Name: Matt Jones (Matt Jones)
Original Date: 2013-12-11T18:41:41Z

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Here's a proposed element definition for the /eml/dataset/citation field. I have preliminarily checked this into EML trunk (r2344) for incorporation in the next release. As it is optional and at the end of the dataset fields, it should be fully backward compatible with prior versions of EML.

<xs:element name="citation" type="cit:CitationType" minOccurs="0" maxOccurs="unbounded">
  <xs:annotation>
    <xs:appinfo>
       <doc:tooltip>Data Citation</doc:tooltip>
       <doc:summary>A citation to articles or products in which the
       dataset is used or referenced.</doc:summary>
       <doc:description>A citation to articles or products in which the
       dataset is used or referenced. The citation element contains 
       general information about a literature resource that has used or
       references this dataset resource.
       </doc:description>
    </xs:appinfo>
  </xs:annotation>
</xs:element>

[mbjones]

Checking this, it has already been merged into both master and the BRANCH_EML_2_2 branch with SHA 1ad87d3. So can be closed and reviewed for release.