Tracking: breaking changes for vNext

[bart-degreed]

This issue tracks breaking changes we'd like to take for the next major version.

• Change detail message in RequestMethodNotAllowedException from "Resource does not support {method} requests." to "Endpoint does not support {method} requests."
• Rename enum StandardQueryStringParameters to QueryStringParameters JsonApiQueryStringParameters (changed due to namespace clash)
• Remove obsolete methods
• Remove suppression on variance in IResourceDefinition<,> and make TId contravariant
• Correct terminology: rename 'secondaryResourceId' in relationship pipeline to 'rightResourceId'
• Remove IJsonApiRequest.BasePath
• Remove EntityFrameworkCoreSupport.Version, along with its usages (for working around EF Core breaking changes and bugs).
• Consistently set IJsonApiRequest.OperationKind from controller actions middleware and rename to WriteOperationKind