Add missing import

This would only happen if a host had a `localhost` domain so I didn't
spot it until today

Author: basepi

hubblestack/utils/stdrec.py

@@ -5,6 +5,8 @@
 This is being tested/used in the generic returner and probably only from
 hstatus exec module (for now).
 '''
+import socket
+
 
 def std_info():
     ''' Generate and return hubble standard host data for use in events: