I also have not seen a total plug and play made specifically for the Tenere. That said, I have one of these.
http://www.revzilla.com/motorcycle/battery-tender-usb-charger
It's not quite plug and play, but if you install a fused SAE outlet, these mount easily with a little Velcro. You then also have the SAE plug for higher current needs, such as battery tenders, air compressors, etc.
http://www.revzilla.com/motorcycle/battery-tender-usb-charger
It's not quite plug and play, but if you install a fused SAE outlet, these mount easily with a little Velcro. You then also have the SAE plug for higher current needs, such as battery tenders, air compressors, etc.