Tuple and array string outputs are confusing in cultures that use a comma as the decimal point

[bamarsha]

Here is the output of displaying some tuples and arrays as strings in the German (de-DE) culture, which uses a comma as the decimal point:

let x = (1.1, 1, 1);
let y = [1.1, 1.0, 1.0];
Message($"{x}");
Message($"{y}");

(1,1, 1, 1)
[1,1,1,1]

It is difficult to tell what the real value of the tuple is, and is actually impossible to tell what the real value of the array is (it's not an array of 4 ints). Intuitively we expect the string output of Q# tuples and arrays to follow Q# syntax, which is why I think using the invariant culture here probably makes sense.

As a note, C# has the same problem with tuples (Q# tuples end up calling C#'s ValueTuple.ToString in the end):

> var x = (1.1, 1.0, 1.0);;
> System.Console.WriteLine(x);;
(1,1, 1, 1)

This is related to #160, but that is probably more easily fixed by setting the current culture to the invariant culture for the duration of the test.