discussion: support for actuators

Actuator support is probably needed soon.

OSMB will need to use actuators with an orchestration.

The eDNA sampler will need to use an actuator. This one could be seen as a sensor for the time beeing, as actuator use with no orchestration will yield more issues to solve.

To use actuators with an orchestration we need to implement a protocol to deliver the control data to the imcu. The actuator config could define some parameters controllable by the orchestration.