How does one include K2 Roles in a K2 Package using the Package and Deployment Tool?  When I click 'Add Items', I don't see any of the K2 Roles.  

It looks like they're added only when referenced in a workflow.  If one populates a drop-down conrtol in a SmartForm with role data -- from the GetRoleUsers method, for example  -- and those roles are not referenced in  a workflow, those roles will not be included in the deployment package.