Add code as an additional field in the indexer model

[cessda-bitbucket-importer]

Original report on BitBucket by Matthew Morris (GitHub: matthew-morris-cessda).

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Currently the long names of repositories are used as unique identifiers of each repository. This makes it harder to do analysis in tools like Kibana. This issue tracks adding a short name, know as a code, that can be easily used to identify each repository.

The code values will be taken from https://vocabularies.cessda.eu/urn/urn:ddi:int.cessda.cv:CdcPublisherNames:2.0.

[cessda-bitbucket-importer]

Original comment by Carsten Thiel (GitHub: schildwaechter).

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Please also add the oai_identifier without any modifications

[cessda-bitbucket-importer]

Original comment by Matthew Morris (GitHub: matthew-morris-cessda).

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The oai identifier is already present as the studyNumber

XPath used: //oai:header/oai:identifier[1]

[cessda-bitbucket-importer]

Original comment by Matthew Morris (GitHub: matthew-morris-cessda).

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Added to the metadata records stored in Elasticsearch

[cessda-bitbucket-importer]

Original comment by John Shepherdson (GitHub: john-shepherdson).

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#197 depended on this being completed