Flexibility to different kinds of motors

[lauraporta]

Is your feature request related to a problem? Please describe.
As for now, the pipeline can only work with analog signals coming from a step motor.
This data is stored as a matlab file generated by rc2_matlab, a matlab software to control the Rollecoaster setup.

Describe the solution you'd like
I'd like to choose between different motor types. This might be done by creating a common analog signals interface to be used by the main derotation pipeline.