Sensors/Actuators cannot be queried until an experiment is started

[szmoore]

ie: You cannot use the "identify" module to ask what sensors/actuators are available, because the arrays of devices are not populated.

This is because the arrays are populated at the same time the devices are initialised.
It can be fixed simply by populating the arrays at the start of the program instead of the start of each experiment. Devices should still be initialised/deinitialised at the start/end of experiments as they are currently.