PowerSwitch III -- universal low voltage trigger

This plugin extends Felix's PowerSwitch II functionality so that any squeezebox client (soft or hard) can utilize a SB Classic (e.g., SB2 or SB3) or Transporter's ir/geek port to send a low volt trigger to, for e.g., power on a multi-zone amp.

Requires an SB2, SB3, or Transporter and an external relay OR a device that can accept a low voltage trigger (~3.5v)--e.g., Felix's circuit design or an amp or powerstrip that can accept a low voltage trigger. For e.g., I'm using an SB3's trigger to power on an outlet on a Belkin Pureav PF60 (which accepts triggers down to 3.3v) to power on a multizone amp being fed streams via squeezeLite (thanks to Triode for best player for headless client) running on a pogoplug (thanks to Andrew for VortexBox Vamp project for modified squeezeplug image and instructions--looking forward to v5 with--hopefully--multiple dac support so one pogoplug can support 4 squeezeLite clients/streams). Turning on squeezelite client turns on amp, and so long as any squeezelite client is on, trigger stays on--regardless of whether SB3 is "on" or sleeping (i.e., displaying time).

Plugin is located at https://github.com/motske/PowerSwitch3
v1 works fine (unless you have more than one SB Classics/Transporters)
Next revision (thanks Kevin M!) should solve multiple SB Classics/Transporter issue and add settings menus to webpage etc.