This code is adapted from pixelherodev paste from IRC

I have added a new fmt option to handle printing slice values ``{v}`` or ``{V}``

While i think it can be made the default, i want your opinion about it

```zig
    var slicea = [0]u32{};
    var sliceb = [3]u32{ 1, 2, 3 };

    std.log.info("Content: {v}", .{slicea});
    std.log.info("Content: {v}", .{sliceb});
```

will print:

```
info: Content: []
info: Content: [1, 2, 3]
```

Question:

Should we drop ``{v}`` and make it the default behavior?