New Feature: Generic Property Bag support

This request is to add a generic Property Bag to the Result type. This enables users to add generic information to a Result object intended to be used later downstream. For example, when an error occurs, I may want to log the error using a unique Id and add that Id to the Result so that I can return the log Id to the caller in addition to the error message.

The property would be an IDictionary and look like this:

`public IDictionary PropertyBag { get; protected set; } = new Dictionary();`