Datastore cleanup (#1892)

* Start Store cleanup

* wip store cleanup

* fix iterables initiating datastores

* handle the possibility of a datastore with no holds and no its own 'create' method

* more cleanup (instances that need more than just client/data)

* missed RoleStore extras

* not sure how eslint didn't catch that tab...

* avoid re-getting the channel we already have...

* cleanup resolvers and refactor them into DataStores

* ^

* and remove

* fix some bugs

* fix lint

* fix documentation maybe?

* formatting

* fix presences

* really fix presences this time

* bad fix was bad... let;s see how bad this one is..

* forgot to save a file

* make presence resolving take userresolveables too

* fix tabs in jsdocs

* fix bad fix from last night that caused issues, with better fix...

* oops

src/client/Client.js

@@ -17,6 +17,7 @@ const ChannelStore = require('../stores/ChannelStore');
 const GuildStore = require('../stores/GuildStore');
 const ClientPresenceStore = require('../stores/ClientPresenceStore');
 const Constants = require('../util/Constants');
+const DataResolver = require('../util/DataResolver');
 const { Error, TypeError, RangeError } = require('../errors');
 
 /**
@@ -292,7 +293,7 @@ class Client extends BaseClient {
    * @returns {Promise<Invite>}
    */
   fetchInvite(invite) {
-    const code = this.resolver.resolveInviteCode(invite);
+    const code = DataResolver.resolveInviteCode(invite);
     return this.api.invites(code).get({ query: { with_counts: true } })
       .then(data => new Invite(this, data));
   }