emailAddress property in examples should be an embedded reference to another Trace rather than a string

[vikhari]

Issue ported from old casework github repo (issue 31). Original author: sbarnum

Examples within the case repo show the emailAddress property of the EmailAccount property bundle as a string.

The EmailAccount property bundle class in UCO (leveraged by CASE) specifies the emailAddress property as a reference to a CyberItem (Trace) object. This follows a pattern where properties representing information that have their own property bundles are captured as references to instances of objects capturing that information rather than embedding it natively. This avoids confusion among producers on where to capture the info and yields greater consistency (one way to do things) and better analytic pivotability.

The examples should be updated appropriately.