feat: introduce cdc client library

[ali-ince]

This PR introduces a CDC client library which will be used by all CDC sourced connectors and provides a client layer to the CDC feature.

I have ported the discussion document into wiki.

[neo-technology-commit-status-publisher]

	Warnings
⚠️	Commit Message 'First draft of a CDC message model and parse.': subject may not be empty, subject may not end with full stop, type may not be empty
⚠️	Commit Message 'Implement client.': subject may not be empty, subject may not end with full stop, type may not be empty

Generated by 🚫 dangerJS against 2c71473

[meistermeier]

I think this looks good in general.
One question: Do we want to have the CDC lib dependent on the parent Kafka project or really make it standalone?

[ali-ince]

@meistermeier I'll extract this into a separate project detached from kafka.

[ali-ince]

also the cdc module is now detached from the parent, making it easier for us to move it independently.