`clear` method should probably be an action?

[HamsterHuey]

https://github.com/gothinkster/react-mobx-realworld-example-app/blob/25e7ed4f07f3f6bbb3bf219f4b1ec60dc0e18544/src/stores/articlesStore.js#L18

Thanks for having this repo as a nice example of MobX + React. I was just browsing through the code and noticed that this method should probably be an action unless I'm missing something? Of course, it probably will work just fine unless you have it set to strict mode, but I figured I'd point it out since pretty much all your other methods across the stores are correctly decorated as actions when they mutate state.

Cheers!