Remove the `keys` array

[IonicaBizau]

Do we we really need the keys array? It can be easily obtained using Object.keys(emoji). 💭

Currently I causes some trouble because I want to check if a word is emoji, so emoji[myWord] will fail for myWord === "keys" (it's not an emoji object but an array).

Looks like it's anyway causing some problems on the Emoji Searcher page:

I'm almost sure there is no :keys: aliased with :-1: but it's just an issue because of the keys object.

So, is the keys array really needed? I would vote to be removed. 🎈

[IonicaBizau]

Obviously, for now I will just delete emoji.keys ❇️ But would be handy not to be there at all.

[muan]

I added keys to provide an ordered list of emojis (in order of category & it's position within a category). Object.keys returns an unordered array, instead of the order it appears in the JSON file. 😔 I know it's weird and unideal but I don't see a way around it.

[IonicaBizau]

Maybe namespace it somehow, then? A suggestion would be to take out the keys array from emojis.json and put it into keys.json and in the js side to do:

module.exports = {
    emojis: require("./emojis")
  , keys: require("./keys")
};

Would make the things smoother. 😁

[muan]

Yup that totally make sense.

[IonicaBizau]

@muan Can I create pull request with this change?