allow COUNTERRATE machines to have no parameters for use in simulation
disable the IOComponent counter rate filter in favour of the machine instance version
install the counter speed calculation filter into its new home
intercept setValue calls for counter rate to give it a change to apply its filter
set the position property for a counter rate machine in a way that is suitable for simulation
added a position device to the COUNTERRATE; this is updated by the rate calculator, not the other way around.