anchor.diff:  When batch registering. There could be potential problems with registering certain UIDs, in that case, there will be
   one or several entries of **errors** under the **registration_result** dictionary.
   
  -
  -| Response Body
  -|
   
   
   Example 1) Successful registration of one device.
  
positive.code:     }
  }
  ....
  Example 2) Registration failed due to invalid Device UID. Note, it still returns a 200 OK HTTP code. No 'registration_result'
  structure is returned in this case.
  ....
  
negative.code:     }
  }
  ....
  
  
  === Device Registration
  