* Adding Helix testing infrastructure

* Update arcade and address feedback

* Fixing tests and cancellation token source issue

Updates for supporting 64 bit linux pin nimbering in Sysfs driver

* Update SysFs naming

* Trying to trick file names

* Added the file names back

* Dispose CancellationTokenSource

* Await task

Otherwise the tokenSource may get disposed prematurely

* Change PinValue to struct

Allows easier interop with raw data and enables us to extend with additional functionality. This will avoid having to add additional APIs for convenience and repeated typing of `PinValue == PinValue.High ? 1 :  0`.

Doesn't impact existing enum usage.

Sample usage:

``` C#
    class Program
    {
        static void Main(string[] args)
        {
            PinValue value = true;
            Console.WriteLine($"True is {value}");
            TestApi(0);
            Console.WriteLine($"Equality is {PinValue.High == true}");
        }

        public static void TestApi(PinValue value)
        {
            Console.WriteLine($"PinValue is {value}");
        }
    }
```

* Ok, so you can't switch a struct. :) Bonus now that you don't have to. There is no such thing as an invalid PinValue anymore.

* Added editconfig file

* Beginning of cleaning

* Added summaries and sorted

* Added callback summaries

* Fixed ordering and switch/case based on feedback

* Basic cleanup in GPIO files

* Basic comment cleanup in GPIO files

* Removed othing lingering words

* Another round of GPIO cleaning

* Removed a couple more words

* Added readonly and updated casing

* Better method grouping and synced constructor summaries

Adding Raspberry Pi Driver

Adding UnixI2cDevice Implementations

Adding Eventing methods to the Unix Driver for Gpio

* Moving Code to the new Api after the ApiReview

* PR Feedback

Change GpioDriver to be an interface and inital implementation of UnixDriver