[Prototype] JSON-ify codelab

[kirjs]

What the issue is about

Right now all the codelab materials are just angular components. It's kinda cool, because angular templates are really powerful and flexible:

There are couple problems:

• It's hard to analyze them: For example how do we approach getting the number of slides in TypeScript milestones?
• The code is UGLY!
• We're stuck with Angular for something that does not need to be Angular, if someone wants to create a course about, let's say react, or just pure JavaScript, they would have to learn Angular
• It's hard to create a UI for building those (Although should be doable with Angular as well)
• it's kind of hard to setup server-side rendering

What we're trying to achieve

As a part of the prototype we're trying to migrate the first milestone (TypeScript) material to JSON, and build an angular component that would render it and insert appropriate components in appropriate places

JSON Structure

This is up to implementor, but I would recommend putting it up to discussion before investing too much time into implementation