Adds a path component to the URI.
A path component is the individual element in the path. For example, in the path "/a/b/c", "a" is a path component, so is "b" and "c".
AddPathComponent automatically adds the required path separator ("/") to the URI.
Use AddPathComponent when you need to append some kind of application data to the URL. For example, it's common for REST services to require an ID to be included in the URL's path.
As example, an Employee web service might expect the URL of this form to retrieve an employee record: