What kind of JavaScript should I learn to get a competitive advantage in the marketplace as a JavaScript developer?

Since you mention your focus on the job hunt, then I will tailor my answer to maximising your chances of a high-paying job in the current job market.
I see five areas of JavaScript on which you can focus. I will list them in order of increasing pay.
- UI Developer
- Framework Developer
- Front-end Engineer
- Design Technologist
- Full Stack Engineer
A UI Developer is someone who likely has used a lot of JQuery in the past and focuses on merely translating UX design specs into functional interactions in the UI. The bulk of your work in this job is HTML and CSS. Your max pay for this job is going to be in the neighbourhood of $120k/yr or $65/hr.
If you want to maximise your value in this market segment, move away from old tools like Bootstrap, Jquery, and Foundation and into frameworks like Angular, Vue, and React. All you need to know is the basics of templates and data binding and in some cases, the animation tools like those in Angular.
Similarly, you can move into esoteric build tools like Pug/Jade for HTML generation and Sass (which isn't all that esoteric anymore) for CSS generation.
A Framework Developer is someone who specialises in a specific framework. Your max pay for this role will be between $120k/yr and $140k/yr, or upwards of $85/hr.
This job requires a far more in-depth understanding of state and state management tools, and all of the peculiarities of your chosen framework. It also requires knowledge of the framework itself. Because, as I have often said, frameworks are the cake mix of the JavaScript world. Angular isn't a thing unto itself. It is a pre-written application that you use. That means that understanding what the app should be used for is valuable knowledge.
As a framework developer, just knowing the framework is enough to set yourself apart. The majority of framework devs learn the framework as a tool. They only know method calls and the like. They never really grok the framework. Grow the framework, and you will be wise.
Beyond that, either you should move into more visual work by studying UX principles and learning visualisation tools like D3 or ThreeJS, or you should move down the stack and become acquainted with NodeJS and ExpressJS. I would say that learning the database is a step too far.
A Front-End Engineer is someone who builds the tools used by other developers. Your pay range for this role is similar to a Framework Developer, but your upper range is higher. With ten years of experience and some open source work under your belt, you could see as much as $200k/yr.
It is the person who architects front-end data structures and state management systems. You will rarely if ever interact with the HTML and CSS, and instead, create tools that will generate HTML and CSS. It is a profoundly CompSci role that requires extensive knowledge of algorithms and data structures. You are, perhaps the most critical person when it comes to performance.
For this role, you really should consider moving down the stack, since you would be well-served to have some influence on the data before it gets to the client. You can dictate data format, optimised calls, and generally unify the front-end with the middleware. Learn Node, Express, or Meteor.
A Design Technologist is a union between a designer and a developer. As such, the pay is much higher than pure developers but doesn't go much higher than developers, with your tax payment in the $180k/yr range.
It is someone with extensive experience and education in Human-Computer Interaction, human perception and psychology, and design. This person also has extensive experience and training in computer science and all aspects of development vis-a-vis the user touch points. It means HTML, CSS, JavaScript, Angular, React, and all considerations therein that affect how the users experience the application. This person is like a UI Engineer on steroids.
Obviously, with such a diverse set of skills, the danger of becoming a jack-of-all-trades, master of none is genuine. As such, do not worry about the middleware. Trust me, it's tempting to play around with Node and Express, but let others do that. Instead, expand your front-end toolkit with Visualisation tools like ThreeJS and D3. Similarly, dive hard into a framework, whether it's Angular or React, and learn it inside out and backwards. Grok that shit!
Also strongly consider beefing up your design bona fides. Do freelance UI/UX, create a portfolio on Behance, take design, industrial design, and psychology night courses. Even if you don't do a lot of your designing, you can act a powerful voice when models are poor or when decisions need to be made.
As a Full Stack Engineer, you're not necessarily the elite of the elite, even though it sometimes seems that way. The pay range illustrates this, with many people earning less than $100k/yr, while others make over $200k/yr.
Instead, your focus no longer involves the full stack, ironic as that may sound. You are a middleware developer. Your playground is Node and Express. Your job is to get data from a database efficiently, format it, send it to the client, and do the same for requests from the client to the database.
To stretch your abilities here, I would focus on different forms of JavaScript development in Node, including reading up on the newest JavaScript. Because unlike on a client, your JavaScript only ever needs run on the server that you own, meaning that you are free to use the absolute most cutting edge features of the language. Similarly, learn all about functional programming, which is the new hotness.
For All Roles
One big way to increase your value is the move up and down the stack conceptually, if not technologically. Having a solid understanding of systems architecture can put yours into an architect position where pay can easily exceed $200k/yr. For this, I highly recommend watching videos from MIT on systems architecture and reading both Cracking the Coding Interview and Cracking the PM Interview. They are excellent primers in the sort of subject matter with which you should familiarise yourself.
The Future
Going forward, I expect that a great deal of JavaScript will be written with tools and languages that compile into vanilla JS. It has the benefits of enforcing coding paradigms in the JavaScript that is run by the client. For example, by using CoffeeScript or TypeScript, better Object-Oriented JavaScript comes out the other end. Or by using Elm or PureScript, better functional JavaScript comes out.
Learning Vanilla JS and how it can be structured is currently the most valuable way to spend your time, but in the future, I expect many difficult and high-paying jobs to become available to those skilled in these compiled languages. Elm will become increasingly popular for complex, client-side applications, while I expect PureScript to rise in popularity for middleware development in Node. You won't find many job listings for these at the moment, but if you should ever find your resume in front of a hiring manager who sees the same writing on the wall as I do, you could jump to the top of the heap with a single word.

Learn Bootstrap responsive web design

Learn Java Script Basics

Learn OOPS and Design pattern  in JavaScript 

Learn Jquery ,  DOM , JSON etc.

Try Framework like ReactJS / AngularJS  

Work on some project which uses all these skills