Add support for turning off signal handler that prints backtrace

[VictorYing]

Adjusted constructor API so that modelers can disable Sparta's signal handlers, since it conflicts with other framework like SST. No change to default behavior.

[klingaard]

Hi Victor, thank you for the submission!

Instead of adding a new construction parameter to the Simulation class, add this behavior to SimulationConfiguration.

Then, move the backtrace_ set handler calls to this function of Simulation:

if(sim_config_->install_signals_handlers) {
   ...
}

Much appreciated!