Support Serial Number lookup in simpleusb

[coolacid]

When there are multiple URIs connected to a repeater, there is a (small) chance that the order of the devices can get mixed up, or, say if you move USB ports, or new machines, or in my case, VM the whole thing.

URIs with eeproms have the ability to store a serial number.

It would be very handy to support selecting the URI by said serial number.