[v3] Separate device configurations from device properties

Right now the subclasses of `Device` mix the static properties of devices with configurable settings. We should clearly separate configurations going forward. I see two options:

1. All configuration properties go in `Acquisition`
2. We add `Instrument.configs` which accepts the same discriminated list allowed in acquisition

I think that 1 is cleaner ultimately and will make the metadata more maintainable. Fortunately this is an easy thing to implement in the v2->v3 upgrader since it should just be copying values from the existing device classes into their corresponding configuration classes, although if it crosses classes that will be complex to implement.