We can't use format with dynamic strings so we can't use gettext
response with format. To format translatable strings easily I've created
a new module so we can use like this:

```
    let literal = i18n("TESTINGx gettext");
    let nonamed_params = i18n_f("TESTING! gettext {} and {}", &["one", "two"]);
    let named_params =i18n_k("TESTING2 gettext {one} and {two}",
                             &[("one", "1"),
                               ("two", "two")]);
```