Add cxx_auto for test build to appease old travis compiler
Add cxx_auto for test build to appease old travis compiler

matthijs/sqlpp11-connector-postgresql,matthijs/sqlpp11-connector-postgresql,cszawisza/sqlpp11-connector-postgresql,cszawisza/sqlpp11-connector-postgresql,matthijs/sqlpp11-connector-postgresql,cszawisza/sqlpp11-connector-postgresql