Better base_shutdown.lua

 * Add built-in support for trigger-based buttons (blue_security_trigger/red_security_trigger)
 * Add built-in support for Lua-defined security shutdown length (SECURITY_LENGTH)
 * Add built-in support for turning on/off lights, brushes, trigger_ff_clips, and trigger_hurts
 * Add some helpful team-oriented trigger definitions in base_teamplay.lua
It's basically the Lua version of extending a function and calling the super function. Saving the old function in a table is just a lame workaround to avoid potential conflicts, because IncludeScript basically removes the concept of file local variables (those Lua core improvements I'm working on will allow the use of 'require', which will solve this issue).

I wrote about it long ago: http://forums.fortress-forever.com/showthread.php?t=23070