Added Event Schema Versioning samples

[oskardudycz]

Shows how to handle basic event schema versioning scenarios using event and stream transformations (e.g. upcasting):

• Simple mapping
  • New not required property
  • New required property
  • Renamed property
• Upcasting
  • Changed Structure
  • New required property
• Downcasters
• Events Transformations
• Stream Transformation
• Summary

See the whole sample at: https://github.com/oskardudycz/EventSourcing.NetCore/tree/main/Sample/EventsVersioning
And details of changes in: #75

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This discussion was created from the release Added Event Schema Versioning samples.