See of some breaking changes can be avoided

[ewoutkramer]

Changes that were needed to use SDK 6.0-alpha1 in Firely Server:

• ElementNodeExtensions.ToScopedNode changed return to IScopedNode, so any code that relied on concrete type needed to be adjusted, either with upcasting, or wrapping in ScopedNode, but that has some side-effects (losing fullUrl, Parent)
• Base no longer implements IReadOnlyDictionary<string, object> causing collection initializers to fail. Example below no longer compiles with error that the type does not implement IEnumerable
  • new Parameters {{"rawResult", new FhirString(json)}};
• SearchParamType moved namespaces, which led to conflicts with FS copy of the enum
• SearchParamDefinition moved namespace, needed to fix references
• In this test, the second ShortPath is equal to Location now as it fails on this behaviour - if it would rather check for IShortPathGenerator it would work as expected
• SourceNode.Valued and SourceNode.Resource changed nullability, so some calls needed !
• FhirTypeAttribute.IsResource removed, some logic needed to be adjusted for that
• Base.NamedChildren removed, replaced with EnumerateElements for the same behaviour
• FhirJsonSerializationSettings gone from ITypedElement.ToJson

We should go over them and see which ones can be avoided or softened. In any case, we should check that these are documented in the change wiki.