Sleep instead of waiting for signal in daemon

The daemon needs to periodically check if the server is still running
so it can exit cleanly instead of waiting for a signal.

Change-Id: I20935773518653916f8ed7d5d3734f7b9e478998
diff --git a/turbo_hipster/cmd/server.py b/turbo_hipster/cmd/server.py
index 0ca6b0a..30d8aaf 100644
--- a/turbo_hipster/cmd/server.py
+++ b/turbo_hipster/cmd/server.py
@@ -21,6 +21,7 @@
 import os
 import signal
 import sys
+import time
 import yaml
 
 from turbo_hipster import worker_server
@@ -53,7 +54,7 @@
 
     while not server.stopped():
         try:
-            signal.pause()
+            time.sleep(3)
         except KeyboardInterrupt:
             print "Ctrl + C: asking tasks to exit nicely...\n"
             server.shutdown()