Updated version of SPARK

[Alexey]

Hello all,

I uploaded an updated version of SPARK. Now it is possible to stop
simulations during a batch run process from SPARK-PL code (from 'begin-
step' and 'end-step' functions). Before, any attempt to stop a
simulation from the code resulted in complete termination of batch run
process. In the updated version of SPARK everything works as it should
be: only the current simulation is stopped but a batch run process
continues.

Alexey