Description of problem:

Return params "modified", "created", "completion_time", "pickup_time" should probably be dateTime.iso8601 opposed to 'string' to be consistent with rest of API.   I believe this is a new API introduced in 5.3, so I don't think there is a concern for backwards compatibility preventing this change.

"pickup_time" behaves as an optional, but it's not marked as such in docs, instead docs state:
  string "pickup_time" - The time the action was picked up or '' if the action was not picked up. Format ->YYYY-MM-dd hh:mm:ss.ms Eg ->2007-06-04 13:58:13.0 



Asking for 3 things
1) Change return date/time types to dateTime.iso8601
2) Update api docs to reflect change
3) Pickup time says it will return '' if action wasn't picked up, when doing a test I'm not always seeing "pickup_time"
Example:  {'archived': 0, 'failed_count': 0, 'name': 'Package Install', 'created': '2009-04-20 12:41:55.0', 'modified': '2009-04-20 12:41:55.0', 'earliest_action': '2009-04-23 12:37:54.0', 'version': '2', 'action_type': 'Package Install', 'id': 50, 'scheduler_user': 'admin', 'successful_count': 0}