Add install instructions and update method name

[ash-jc-allen]

Hey @JonPurvis, I love the new package! I'm going to be installing it in my own projects 😄

I was just giving it a spin before I wrote a blog post about it, and I noticed a couple of things in the docs. There didn't seem to be any instructions on how to install the package. And I think the method name mentioned didn't seem to be the same as the one in the plugin's code.

I've updated both of these (hopefully correctly). But please feel free to close the PR if you don't think these changes are needed! 😄

[JonPurvis]

Hey @ash-jc-allen 👋

Thanks for checking it out and thanks for sorting out some really simple stuff I missed 😆

The method name in the readme was actually what it was originally going to be called, before I changed my mind 😆 I forgot I had it referenced in the docs. I'll get this PR merged!

[ash-jc-allen]

Hey, it's no problemo, I'm glad I could lend a hand!

And I had a feeling that was the case with the naming. I do it all the time haha 😄