Added CORS allowed methods to spring configuration

[aaronzi]

Currently, only the allowed origins can be configured. However, allowed methods are also needed to send requests to the BaSyx SDK from the browser. By default GET, HEAD and POST are allowed which is not enough when looking at the API specs. The BaSyx AAS Web UI needs for example PATCH to write values to a Property.

[FrankSchnicke]

Thanks a lot for providing this extension! However, I moved the current content of the Readme.md to a separate file (https://github.com/eclipse-basyx/basyx-java-server-sdk/blob/main/docs/Components.md), thus creating a merge conflict.

Would it be possible to adapt your PR to add the new documentation to Components.md instead?

[aaronzi]

@FrankSchnicke I adapted the PR according to the changes to the documentation.

[FrankSchnicke]

Thanks a lot!