[Ovmsdev] New polling framework example

[solterra at kezarnet.com]

I'm working on the Toyota eTNGA vehicle integration and had a vehicle 
module nearly ready to merge last year. Unfortunately, my car broke 
down, and I've only recently gotten a new one.

It seems that the polling framework has changed quite a bit since then. 
Could someone point me toward a good example of the new framework so I 
can start converting my module?

Thanks in advance for your help!