Write acceptance tests for data parsing

[smspillaz]

The following acceptance tests need to be written

• [x] Following fields can be extracted from an XML file
  • [x] country
  • [x] pmid
  • [x] ISSN
  • [x] pubDate
  • [x] author
• [x] Warnings are emitted about documents which are clearly invalid
• [x] Attempting to parse document with the following missing fields still produces a valid JSON object
  • [x] Paper title
  • [x] Author
  • [ ] Category
  • [ ] Retraction Reason
  • [x] Country of Origin
  • [x] Publication Date
  • [x] Retraction Date
• [x] Warning emitted where document does not have at least one non-mandatory field
• [x] Set bits for partially specified dates in documents
  • [x] Only year specified
  • [x] Month and year specified
• [x] Scrubbing of malformed text
• [x] Warning emitted where contradictory field entries encountered (dates)

Estimated time: 1 hours Actual time: 2.5 hours