Deriving copy for PeripheralID

[ratmice]

From what I can tell, PeripheralId is a newtype around a platform defined type

winrtble ~ PeripheralId(Uuid)
bluez | corebluetooth ~ PeripheralId(BDAddr)

It seems that both BDAddr, and Uuid types are copy,
So in theory it seems currently it is possible to make PeripheralId copy, as well.
I can't think of a reason why something which is truly just an Id shouldn't be copy, but perhaps i'm not creative enough.

So I figured i'd ask before just sending a PR if there is any reason or objections to making it so.

[qwandor]

On some other platforms it will be a larger type, e.g. the draft WebBluetooth implementation in #204 uses a String for PeripheralId. I don't remember what the Android implementation was going to do. I was also thinking of changing the Linux implementation to use a wrapper around a string (the D-Bus path), because at the moment it has to convert back and forth all the time.

So although we could currently make PeripheralId implement Copy, I'd rather not do that now only to remove it again later when we add more platforms.