Update dependencies to major versions

[rocktimsaikia]

Most of the dependencies used in the template are outdated now with some of them having major version updates. I think it's high time to update these dependencies.

I was recently using this generator for a project without even checking if everything was up-to-date. But I did find out after 3 hours that all dependencies were outdated when I completed the whole project at yeoman-generator v3.1.1. 😢 . Then I had to update every dependency and work on that again.

If any maintainer approves this issue . Can I make a pull request on it?