Adding a try, except to prontserve's print queue loop to try and flush out some bugs.

prontserve.py

@@ -580,6 +580,7 @@ class Prontserve(pronsole.pronsole, EventEmitter):
     # A better solution would be one in which a print_finised event could be 
     # listend for asynchronously without polling.
     p = self.p
+    try:
       if self.printing_jobs and p.printing == False and p.online:
         if self.current_job != None:
           self.update_job_progress(100)
@@ -604,6 +605,9 @@ class Prontserve(pronsole.pronsole, EventEmitter):
       # Updating the job progress
       self.update_job_progress(self.print_progress())
 
+    except Exception as ex:
+      print traceback.format_exc()
+
     #print "print loop"
     next_timeout = time.time() + 0.3
     gen.Task(self.ioloop.add_timeout(next_timeout, self.run_print_queue_loop))