Add Support for Insteon iMeter Solo and SynchroLinc

I coded this without having the devices on hand, so I can't be sure it works.  I was only able to test to make sure that the MH code was stable.

I added support for everything I know about these devices, but there may be features that I was not able to discover from my web searches.

If anyone has one of these, I would be interested to know how this works.  Both devices are very different from the normal Insteon type devices.

Fixes #372