Add a "From zero to hero" contributor roadmap article to https://pulsar.apache.org/contribute/contributor-roadmap

[visortelle]

Imagine that you are a Pulsar user or interested in data streaming in general and would like to contribute to some related open-source project.

You have some prior programming experience but you've worked on other kinds of projects and never developed distributed streaming systems.

The current documentation doesn't describe the prior knowledge list recommended to contribute to Pulsar.

Having a clear roadmap of what to learn and where to start would bring more contributors to the project.

It may have a similar format:

• Java
  Recommended resources:
  ...
• Concurrency and Parallelism
  Recommended resources:
  ...
• Networking
  Recommended resources:
  ...
• Data streaming
  Recommended resources:
  ...
• Cyber-security
  Recommended resources:
  ...
• Storage and Bookkeeper
  Recommended resources:
  ...
• Pulsar internals
  Recommended resources:
  ...
• Important libraries to know
  • Netty
  • Jetty
  • Lombok
    ...
• Issue list for starting contributing
  ...

Of course, it takes time to learn these things and can add some additional load on the PR reviewers' shoulders at first. But it also could help to grow a new wave of contributors who are loyal to the project from the beginning, which is important for growing the Pulsar contributors community.

Mailing list thread: https://lists.apache.org/thread/99kych4r4lcw33qs49bwk9zxmss8vggl

[asafm]

Where would you like to place this?

[visortelle]

Probably Contribute -> Development -> Developer Roadmap

[asafm]

Cool.
Maybe "Prerequisite Knowledge"? or "Recommended Knowledge"?

[visortelle]

I think “Recommended ” fits better here.

Therefore “Recommended Knowledge” until we haven't better options.