Docs: Add roadmap

[ikolomi]

Describe the feature

We should to expose a some form of planned roadmap that should contain versions, approximate dates and major features.
This has many benefits such as:

• Conveying a strong commitment for continuing developing and maintaining
• Keeping the contributors aware of when their contributions will be integrated
• Allowing potential users to plan
• Keeping the interest high

Use Case

See the description

Proposed Solution

A short summary with the versions, approx. dates and the major features could be provided in the README.md.
This is much better than exposing the Project Roadmap view, as it contains too much information that can bog down the potential readers.

Other Information

No response

Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

Client version used

Dont care

Environment details (OS name and version, etc.)

Dont care