[V3] Implement new Concept Exercise: constructors

[kristinaborn]

This issue describes how to implement the constructors concept exercise for the JavaScript track.

Getting started

Please please please read the docs before starting. Posting PRs without reading these docs will be a lot more frustrating for you during the review cycle, and exhaust Exercism's maintainers' time. So, before diving into the implementation, please read up on the following documents:

• The features of v3.
• Rationale for v3.
• What are concept exercise and how they are structured?

Please also watch the following video:

• The Anatomy of a Concept Exercise.

Goal

This exercise aims to teach students how constructors are implemented in JavaScript.

Learning objectives

• Know that constructors are regular functions
• Know how to use built-in constructors
• Know how to define and use custom constructors
• Know how to use the constructor class method
• Understand the importance of the new keyword

Out of scope

• Performance of built-in constructors vs. object literals

Concepts

• constructors

Prerequisites

• any data type used in the exercise
• inheritance
• classes

After

• Performance of built-in constructors vs. object literals

Help

If you have any questions while implementing the exercise, please post the questions as comments in this issue.

[junedev]

I am closing this issue because we decided to cut concepts/concept exercises differently. See #951 (comment) for details. Constructors are now part of the classes concept (#1015).