[oozie] Workflow editor protocol - fields should not be serialized

Communication between the front end and back end is not clearly defined for the more complex fields. Because of this, the logic on the front end is very particular for both the jobsub and oozie apps.

Example:
The file field is stored as a JSON list (IE: ['ex 1', 'ex 2', ...]).

Improvements:

1. Backend should send a deserialized list to the front end.
2. Frontend should only change the representation of the values it receives and values it sends.
3. Frontend should send back a deserialized list to the server.