CRM-13966 - Add method to Core_Form for contactRef fields
CRM-13966 - Workaround for ui.dialog & select2 conflict
CRM-13966 - Improve search widget style
CRM-13966 - Migrate activity source_contact_id to use select2
CRM-13966 - Change contactRef to entityRef
CRM-13966 - entityRef - Render frozen text as link when appropriate
CRM-13966 - select2 - set default & allowClear from markup
Merge pull request #2451 from colemanw/contactRef

Contact ref