v1.1.0 - Minor improvements

Minor changes to improve general use, and for a more graceful management of Product / Tariffs going into 'end of life'.

• Move the product / tariff / region out of the URL to a parameter object
• Permit 'import' (or 'export') call to be optional
• Prevent array update unless API call return is complete and correct
• Provide call update debug information stored to context
• Provide product (from call and 'market-available' list) stored to context

Note that product and tariff settings are now held in a JSON object in the first 'Tariff' node