Add exit signal for debugging

bilby/core/sampler/ptemcee.py

@@ -504,6 +504,7 @@ class Ptemcee(MCMCSampler):
         if getattr(self, "pool", None):
             logger.info("Closing pool")
             self.pool.close()
+        logger.info("Exit on signal {}".format(self.exit_code))
         sys.exit(self.exit_code)
 
     def write_current_state(self, plot=True):