CC-2758: Make airtime-install script Debian/Ubuntu compatible

-further tweaks

python_apps/pypo/install/pypo-uninitialize.py

@@ -8,8 +8,12 @@ if os.geteuid() != 0:
 
 try:      
     #stop pypo and liquidsoap processes
-    print "Waiting for pypo processes to stop..."
-    p = Popen("/etc/init.d/airtime-playout stop", shell=True)
-    sts = os.waitpid(p.pid, 0)[1]
+    print "Waiting for pypo processes to stop...",
+    if (os.path.exists('/etc/init.d/airtime-playout')):
+        p = Popen("/etc/init.d/airtime-playout stop", shell=True)
+        sts = os.waitpid(p.pid, 0)[1]
+        print "OK"
+    else:
+        print "Wasn't running"
 except Exception, e:
     print e