Provide method for accessing jsonld details of a specific commit

e.g. this for accessing metadata on a commit doesn't work atm:

curl -X 'GET' \
  'https://dluhc-pmd5-prototype.publishmydata.com/data/Planning-Applications-Decisions/release/Developments-England/revision/1/commit/1' \
  -H 'accept: application/json'

This would be useful to support this bit of the UI where it would be useful to list whether a commit added/deleted/changed rows:

Swirrl / datahost-prototypes

Provide method for accessing jsonld details of a specific commit #395