Ctrl-C does not cleanly terminate multithread operations

[KSchopmeyer]

Some of the operations (cimping, explorer, sweep) are multithreaded, creating many threads to accomplish there tasks more rapidly. Normally a Cntrl_C should immediatly terminate the operation.

However, it does not since we are not passing the kill information on to each thread but depending on the thread to terminate. This works fairly well in most cases except for the sweep where a very large sweep does not die for some time after a ctrl_c, depending on the range of the sweep.