Base Emoji class for ReactionEmoji and renamed GuildEmoji classes (#2230)

* feat: create base Emoji class for ReactionEmoji and new GuildEmoji

* rename EmojiStore to GuildEmojiStore to account for the new class' name

src/structures/ReactionEmoji.js

@@ -1,49 +1,19 @@
+const Emoji = require('./Emoji');
+
 /**
  * Represents a limited emoji set used for both custom and unicode emojis. Custom emojis
  * will use this class opposed to the Emoji class when the client doesn't know enough
  * information about them.
+ * @extends {Emoji}
  */
-class ReactionEmoji {
-  constructor(reaction, name, id) {
+class ReactionEmoji extends Emoji {
+  constructor(reaction, emoji) {
+    super(reaction.message.client, emoji);
     /**
      * The message reaction this emoji refers to
      * @type {MessageReaction}
      */
     this.reaction = reaction;
-
-    /**
-     * The name of this reaction emoji
-     * @type {string}
-     */
-    this.name = name;
-
-    /**
-     * The ID of this reaction emoji
-     * @type {?Snowflake}
-     */
-    this.id = id;
-  }
-
-  /**
-   * The identifier of this emoji, used for message reactions
-   * @type {string}
-   * @readonly
-   */
-  get identifier() {
-    if (this.id) return `${this.name}:${this.id}`;
-    return encodeURIComponent(this.name);
-  }
-
-  /**
-   * When concatenated with a string, this automatically returns the text required to form a graphical emoji on Discord
-   * instead of the ReactionEmoji object.
-   * @returns {string}
-   * @example
-   * // Send the emoji used in a reaction to the channel the reaction is part of
-   * reaction.message.channel.send(`The emoji used was: ${reaction.emoji}`);
-   */
-  toString() {
-    return this.id ? `<:${this.name}:${this.id}>` : this.name;
   }
 }