We've updated our API versioning process

We've updated the information in our API reference on how we do API versioning at Duffel. API versioning allows us to make important changes to improve our API without impacting your experience with it. Some of the important areas that we've updated are how long versions will be available for, what different categories of changes are, and how migrating from one version to another will work.

Our current version is still `beta`. There is nothing that you need to change with your integration.