Typos (minor) in the readme.

[chaseoneill]

I fixed 2 typos in the readme.

If you want, I can submit a PR for them.

First was line 853 YOur -> Your
Second was line 1067 alread -> already

Thanks for this guide, it is great!

[mefellows]

So sorry I missed this, yes I'd happily accept a PR (Hooking this repo up to our slack alerts now)