Allow users to select the algorithm in feature computation

[nicola-corbellini]

Currently, all the features apply all the available algorithms.

As discussed with @sanketsabharwal, we could provide the user with a "method" parameter in the __call__ function to select the algorithm.
E.g., an option could be:

smoothness = Smoothness()

sparc = smoothness([motion_data], method="sparc")

and if None applies all the algorithms.

smoothness = Smoothness()

sparc, jerk = smoothness([motion_data], method=None)

[sanketsabharwal]

@nicola-corbellini we must discuss this internally how and when we want to implement this.

[nicola-corbellini]

Sure, we can have a call later this afternoon or on Monday to have some proposals to talk about it in the dev meeting we have on Tuesday