To add Learning Roadmap on Landing Page Section

[isarojdahal]

Currently lead by @theanupambista

[theanupambista]

I have just created the basic structure for homepage roadmap. Let me know if there can be improvements.

For making roadmap diagrams I have confusion which to use

1. I have found mermaid in docusaurus documentation.
   https://docusaurus.io/docs/next/markdown-features/diagrams
2. Just simply use images
3. embed roadmap by creating in other websites such as canva
   or there can be other better ways let me know

[isarojdahal]

I have just created the basic structure for homepage roadmap. Let me know if there can be improvements.

For making roadmap diagrams I have confusion which to use

1. I have found mermaid in docusaurus documentation.
   https://docusaurus.io/docs/next/markdown-features/diagrams
2. Just simply use images
3. embed roadmap by creating in other websites such as canva
   or there can be other better ways let me know

Currently the docusaurus diagrams is in Canary version; not sure, how much changes/updates will be there in upcoming days. For now, lets use coded format (using cards and list)

[theanupambista]

The version we are using 3.5.2, docusaurus diagram released and maintained. I think Canary version is upcoming version.