Feature: A new option in systemCall to execute the call with the master processor only

In OpenFOAM 1712, systemCall function object can be created and used to execute system calls.

In parallel simulations, however, the same systemCall is executed for each processor. Yet arguably, the usual desire is to make a single call per simulation (e.g. sending an informative e-mail about the simulation at some point).

Although a shell script wrapping the calls for a single processor should be enough, IMHO, an option which can naturally limit systemCall to a single processor might be useful for those who are not familiar with programming.

Kind regards