Introduce actors besides sensors.

[Idorobots]

Reading values is cool and all, but it would be really nice to be able to finally do something with those values.

A sensor is a set of readings that can be configured individually and retrieved in bulk via the API. Readings display on the UI via the associated widgetConfig.

An actor should be a set of endpoints that can be configured individually and triggered individually via the API. Depending on the type of the endpoint a different schema of data will be required. It should be possible to retrieve endpoints' current state via the API as well. Endpoints should also have an associated widgetConfig of a widget able to display the endpoints state.

Some examples:

• on/off relay switch - accepts the state (either open or closed) and triggers an external relay switch,
• display - accepts text to display on an attached screen (maybe a bitmap as well?),
• network-attached IR blaster - with configurable remote controller widgets,
• servo - accepts rotation angle.