GuildEmoji: Move all role related functions to a separate store (#2271)

* Prepare to work on moving all role functions to a Store

And yes, this is *another* patch branch cause I messed up my master branch to hell

* Move all emoji role related functions to its own store
Tested everything and it works! (With a reload of the client)
Also had to change a value in DataStore#holds
holds.name for GuildEmojis would return the emoji name instead of the class name

* New Line

* Thanks JS for circular dependency!
Because we can't have nice things...

* Do space's request

* Fix equals

* Fix space's point.

Raw API data has the role property as an array of IDs

src/index.js

@@ -28,6 +28,7 @@ module.exports = {
   ClientPresenceStore: require('./stores/ClientPresenceStore'),
   GuildChannelStore: require('./stores/GuildChannelStore'),
   GuildEmojiStore: require('./stores/GuildEmojiStore'),
+  GuildEmojiRoleStore: require('./stores/GuildEmojiRoleStore'),
   GuildMemberStore: require('./stores/GuildMemberStore'),
   GuildMemberRoleStore: require('./stores/GuildMemberRoleStore'),
   GuildStore: require('./stores/GuildStore'),