allow parameters for restart effector, including children and the machine for SoftwareProcess.restart;

if this model is sensible i'd like to apply it more widely to effectors, to allow parameters to tune behaviour.
(eg for stop, to allow controlling whether it is the machine or just the process which is stopped,
and on start, to allow forcing reinstall)
the approach here moves away from using the methods as the implementation of the effector, primarily to support optional parameters.

the complexity comes because we already had the methods, and they are useful for callers in  a java context.  but my preference would be to move away from methods as effectors altogether, so all effector operations become first class objects.  it is more weight, having classes for each, but the benefits outweigh it in my view:  it makes it easy to add parameters, and it makes it easy to apply effector implementations to multiple entities.  (we could even get rid of the EntityProxy!)

so while you're right that this `StopEffectorBody` could be replaced with a general `WarnIfParametersGivenEffectorWrapper`, the intention is that a subclass entity could redefine the stop effector to have a subclass which does more interesting things with effectors.