Please add Somfy ZRTSI to zwave models

[Dean Roddey]

I looked at it and it's done with the underlying handler for dimmers, because it has the same needs and I didn't want to have to create something just for this. I will either need to make that handler more flexible so it doesn't necessarily create lighting oriented field names, or create another one for blinds controllers or something. In the meantime it'll have to say like it is.