Merge branch 'release/1.6.8'
Add release notes 1.6.8
Issue #444 - BulkDataService client now handles cursor param
Issue #445 - Consider the case of empty string for a value

* The value of the map could be an empty string, if that is the case we
  just skip that cell
Issue #446 - Set default values for new SurveyInstances

* Set 1 for `userID` and a generated UUID for `uuid` to avoid problems
  when exporting the data
Merge branch 'hotfix/446'
Add release notes for 1.6.8.1
Merge branch 'master' into develop
Merge branch 'develop' into feature/231-229