3.0.0

• This library now requires .NET Framework 4.6.1 or greater or .NET Standard
  2.0 or greater.
• .NET 5.0 was added as a target framework.
• System.Text.Json is now used for serializing and deserializing JSON.
  If you are serializing the objects yourself, the Newtonsoft.Json
  attributes have been removed and you will need to switch to
  System.Text.Json.
• When creating a Transaction object, you may now use init-only properties
  rather than constructor parameters.
• You may now create WebServiceClient as a typed client with
  IHttpClientFactory in .NET Core 2.1+.
• Exception objects now correctly implement ISerializable.
• The Warnings properties on the response models are now an
  IReadOnlyList<Warning> rather than an IList<Warning>.
• The Names properties on NamedEntity models are now
  IReadOnlyDictionary<string, string>.
• The Subdivisions property on MaxMind.MinFraud.Response.IPAddress is now
  an IReadOnlyList<Subdivision>.
• GeoNameId properties on NamedEntity models are now long? rather than
  int? to match the underlying database.