Adapted model in order to better manage harvested data
RestAPI: enabled command reply as API response.
Harvester plugin: extended data extraction to better suit RestAPI response
Batch of small fixes and enhancements:
 - corrected LOG destinations on [Trigger|Command|Reaction]Persistence save methods
 - added capability to remove tuples' elements
 - corrected result colection in Harvester
 - small fixes in RestAPI
 - added shutdown capability through RestAPI
Core-347: add "consumption" behavior to ElectricDevice
 - modified model and core to support the new behavior.
 - adapted Base-Objects and RestAPI plugins