multiple uses of the same tag should result in the tag contents being merged

[pacharanero]

For example:, if PC/ was re-used further down the document then the data should be merged under just one instance of the field:

PC/
cough

PMH/
asthma

PC/
discoloured sputum

should result in:

{
  "presenting-complaint": ["cough", "discoloured sputum"],
  "past-medical-history": "asthma"
}

as opposed to:

{
  "presenting-complaint": "cough",
  "past-medical-history": "asthma",
  "presenting-complaint": "discoloured sputum"
}