Make the constructor case-insensitive

If I run the following:
```
console.log("Globalize curr with currencyFormatter, ja-jp:" + Globalize("ja-jp").currencyFormatter("BGN", {
compact: "short"
})(112310));

console.log("Globalize curr with currencyFormatter, ja-JP:" + Globalize("ja-JP").currencyFormatter("BGN", {
compact: "short"
})(112310));
```
I get
```
Globalize curr with currencyFormatter, ja:BGN 112K
Globalize curr with currencyFormatter, ja:BGN 11万
```

the latter of which is correct. I think the constructor should automatically capitalise the locale code correctly as this feels like something that could catch a lot of people out (I might be happy to raise a PR myself)