Range implementing IEnumerable<int>

[lucasteles]

I think would be great to have a simpler way to define a collection range outside Enumerable.Range, which is not from-to, It is from and size.

A way to do that today is using the Range data type.

foreach (var n in 1..10)
    Console.WriteLine(n);

var things = (1..10)
            .AsEnumerable()
            .Select(GetStuff)
            .Where(x => x.Length > 0);

public static class RangeExtensions {
    public static IEnumerator<int> GetEnumerator(this Range range) => 
        range.AsEnumerable().GetEnumerator();
    public static IEnumerable<int> AsEnumerable(this Range range) => 
        Enumerable.Range(range.Start.Value, range.End.Value - range.Start.Value);
}

If Range implements IEnumerable this could work nice, dropping the use of .AsEnumerable() and gaining a cool syntax to define rage values

[CyrusNajmabadi]

Transferring to runtime.

[hez2010]

Duplicates #462