Include the poweroff support in ogOperation

This new patch allows us to turn off the linux machine using poweroff binary
or in OpenGnsys client case, use the specific script.

src/linux/ogOperations.py

@@ -1,5 +1,11 @@
+import os
+import subprocess
+
 def poweroff():
-	print 'APAGADO'
+	if os.path.exists('/scripts/oginit'):
+		subprocess.call('source /opt/opengnsys/etc/preinit/loadenviron.sh; /opt/opengnsys/scripts/poweroff', shell=True)
+	else:
+		subprocess.call(['/sbin/poweroff'])
 
 def reboot():
 	print 'REBOOT'