Revived Support for Insteon Thermostat

This is only an update of the prior code to make it work with the current Insteon code as well as to add support for new i2 devices.  I2 thermostats will not work until the i2 code is merged in.  

In order to allow it to be added to the upcoming stable release, no additional features have been added.  

The next version of this support will have significant revisions and feature additions for the i2 devices.