Add /joc/api/settings REST Web Service API

Current Situation

• The operation to download/upload settings is available from the JOC Cockpit GUI in the Settings page.
• The GUI makes use of a number of internal web services:
  • /joc/api/configuration/
  • /joc/api/configuration/save

Feature

• A new web service is provided that is more easily usable by external clients to read and to store settings:
• read: /joc/api/settings
• store: /joc/api/settings/store
• Note: no delete operation is offered