Add support to edit emojis (#1142)

* Add support to edit emojis

* Fixes for coding style.

* Add and use guildEmoji constants for updateEmoji

* Just use the Constant

* Fix typo in edit documentation

* Specify property types

* Fix ridiculous typo.

* Update Emoji.js

src/structures/Emoji.js

@@ -101,6 +101,27 @@ class Emoji {
     return encodeURIComponent(this.name);
   }
 
+  /**
+   * Data for editing an emoji
+   * @typedef {Object} EmojiEditData
+   * @property {string} [name] The name of the emoji
+   * @property {Collection<string, Role>|Array<string|Role>} [roles] Roles to restrict emoji to
+   */
+
+  /**
+   * Edits the emoji
+   * @param {EmojiEditData} data The new data for the emoji
+   * @returns {Promise<Emoji>}
+   * @example
+   * // edit a emoji
+   * emoji.edit({name: 'newemoji'})
+   *  .then(e => console.log(`Edited emoji ${e}`))
+   *  .catch(console.error);
+   */
+  edit(data) {
+    return this.client.rest.methods.updateEmoji(this, data);
+  }
+
   /**
    * When concatenated with a string, this automatically returns the emoji mention rather than the object.
    * @returns {string}