Include section on how to create transient objects

[mvonballmo]

C# offers support for object-initialization, including init and required properties that allow a user to create immutable objects with a very convenient syntax.

Avoid using factories to create objects that are better created with new().

Drawbacks:

• You can't use object-initialization syntax
• It's difficult to find references to where these objects are created

For example, if you have a database layer that lets you create and save objects, an API that returns a new object is not ideal.