Equals updates (#987)

* Docs update

Changed the param names and param descriptions to be consistent.

* Added === comparison

Changed Presence.equals and Game.equals to first compare using ===

* Collection.equals fix

Now returns false when collection is undefined, instead of crashing
💯

src/structures/User.js

@@ -230,7 +230,7 @@ class User {
   /**
    * Checks if the user is equal to another. It compares username, ID, discriminator, status and the game being played.
    * It is recommended to compare equality by using `user.id === user2.id` unless you want to compare all properties.
-   * @param {User} user The user to compare
+   * @param {User} user User to compare with
    * @returns {boolean}
    */
   equals(user) {