If it is supplied a user object path, this procedure returns an
isSelf value of 0 or 1 indicating whether the user summiting the
request == the supplied user object.
This procedure is intended to support a common requirement of
control panels and self service portals, which is the ability to
determine if an action is being performed on the logged on users
object. Examples include whether to display a change password UI or
a reset password UI, or whether to allow an admin user to delete
themselves or not.