Updated to fix recent changes on Riot's end. Also minor code cleanup.

There is a somewhat small inconsistency on Riot's part that I'm sure would make the code bug out.

On calling `lol-static-data-v1.2`: If you call it on `na`, the correct URL should be:
`https://na.api.pvp.net/api/lol/static-data/na/v1.2/champion?api_key=blah`

However, if you want to call it on `kr`, the correct URL, according to Riot, is:
`https://prod.api.pvp.net/api/lol/static-data/kr/v1.2/champion?api_key=blah`

(notice how it's not `kr.prod.api`)

I'm pretty sure they just overlooked this and it will eventually be fixed (and so the code should fix itself). Because every other region follows that convention.

Aside from that minor little thing which probably will very little use case, the tests pass.