{ id: 'flowdock-flow-id',
  name: 'Flow Name',
  parameterized_name: 'flow-name',

  ...

  users:
   [ { id: 12345,
       nick: 'Leo',
       ...
       last_activity: 1426075323840,
     },
     { id: 131464,
       nick: 'Jason',
       ...
       last_activity: 1426117969055,
      } ],
...
}