added Base::is_lab_staff() method; access to lab test history now restricted to lab staff; C::Roles::DataMap::user_locations_map uses user_locations table instead of email_contacts table so that non-network users get a new diagnosis list}
git-svn-id: https://jti.org.uk/svn/hmds_lims/trunk@1167 4177bd82-f056-0410-812d-caef170e3fa0
