ZWaveJS.NET does not support multiple drivers

[spudwebb]

I'm trying to control multiple instances of ZWave JS from the same C# program. For this, I initialize multiple instances of the ZWaveJS.NET.Driver class but as soon as I initialize a second instance, the Driver.Instance of the first instance is overwritten because Driver.Instance is static:

https://github.com/zwave-js/ZWaveJS.NET/blob/6c3db915019895bd99a28edd7370bec5866ecfdb/Visual%20Studio%20Projects/ZWaveJS.NET/ZWaveJS.NET/Driver.cs#L14

So I think we should refactor the library so that it does not use a singleton pattern for the Driver class. Do you agree ?