Add ability to modify settings from device eg by voice or touch screen

[krisgesling]

Currently Skill settings are pulled down from the server to the device, there is no ability to set these from the device and update them on the server. This prevents any Skill from adding voice configuration of itself.

It's been suggested that this:

• be limited to only upload settings that exist in the settingsmeta - thereby allowing skills to have private (local only) settings.
• validate locally that a setting value is the correct format for the field type defined in the settingsmeta file