Rework flow scripts into user scripts

scripts/callbacks/user_scripts/periodic/default.lua

@@ -0,0 +1,42 @@
+--
+-- (C) 2016-17 - ntop.org
+--
+
+--
+-- NOTE: You should *NOT* delete/edit this file. Create a new file in this directory instead.
+--
+
+-- ########################################################
+--
+--    < Lua Virtual Machine - periodic >
+--
+-- The callbacks listed below are executed periodically.
+-- Usually these callbacks cannot modify internal objects status because of
+-- missing thread synchronization logic.
+--
+-- ########################################################
+
+local dirs = ntop.getDirs()
+package.path = dirs.installdir .. "/scripts/lua/modules/?.lua;" .. package.path
+require("lua_utils")
+
+-- Enable debug here
+local trace_enabled = false
+
+local callbacks = {}
+
+-- ########################################################
+
+--
+-- This callback is called periodically for all active flows
+-- Add here housekeeping of periodic activities you want to
+-- perform in a flow.
+-- Flow callbacks can be accesed via "flow" register.
+--
+function callbacks.flowUpdate()
+   if(trace_enabled) then print("flowUpdate()\n") end
+end
+
+-- ########################################################
+
+return callbacks