It's probably better to have a new description field for this

but list all the properties instead

TODO: the GUI will have to make it a float too

Notes:
  * Input format changed (Source.part now is a full name)
  * __init__ must handle complex data structures for processingTime & interarrivalTime instead of having flat parameters
  * type conversion must be performed ("1" != 1), probably we can assume json has correct type and have the gui produce proper json