flimflam: add "psk" security as a way to specify either "wpa" or "rsn"

test/configure-wifi

 #!/usr/bin/python
 
 import pprint, sys
 import dbus, flimflam
 
 if (len(sys.argv) < 2):
     print "Usage: %s <ssid> [passphrase] [security]" % (sys.argv[0])
     sys.exit(1)
 
 print "Attempting to configure service %s" % (sys.argv[1])
 
 flim = flimflam.FlimFlam(dbus.SystemBus())
 
 ssid = sys.argv[1]
 if len(sys.argv) > 2:
     if len(sys.argv) > 3:
         security = sys.argv[3]
     else:
-        security = "rsn"
+        security = "psk"
     passphrase = sys.argv[2]
 else:
     security = "none"
     passphrase = ""
 
 flim.manager.ConfigureWifiService(({
       "Type" : "wifi",
       "Mode" : "managed",
       "SSID" : ssid,
       "Security" : security,
       "Passphrase" : passphrase }))