Migrate Website to Docusaurus 2 Alpha

[Gauravsaha-97]

Issue Body:

Hi there! The Docusaurus team is currently developing Docusaurus 2 and are almost done with an MVP that doesn't include translations and versioning features, which means there's feature parity with your website's current usage of Docusaurus.

Docusaurus 2 brings about many improvements:

• Client-side rendering with prerendering (site renders without JavaScript!)
• More flexible appearance - Customizable layouts, CSS modules, etc
• Embeddable interactive React components within markdown via MDX

I will be helping you migrate and be the POC throughout the migration process. Let me know what you think!

cc @yangshun @wgao19

[phated]

I'd love help with this! I was tracking the v2 for awhile but haven't touched this website in quite some time.

[yangshun]

Thank you @phated! May we know the reason for leaving the home page as a standalone HTML instead of building it into the Docusaurus website? I noticed this was the case for the Docusaurus 1 website as well but just wondering the rationale.

[phated]

@yangshun the original website was created from a purchased theme and none of us have really worked on it. However, my friend is a talented UI designer/dev and is currently working to port her React redesign here—which is what inspired me to get this migration completed.

We hope to have more to show off soon and I'll send an updated showcase!

[yangshun]

Thank you! Do let us know how we can help out (code reviews, UI suggestions, etc)! If you like, you could show us the redesign mocks we can comment on the feasibility too!

Looking forward to showcasing gulpjs.com on Docusaurus v2 showcase ❤️