build examples from inside source tree rather than using installed libs
build examples from inside source tree rather than using installed libs

mongodb/mongo-cxx-driver,xdg/mongo-cxx-driver,acmorrow/mongo-cxx-driver,acmorrow/mongo-cxx-driver,mongodb/mongo-cxx-driver,acmorrow/mongo-cxx-driver,xdg/mongo-cxx-driver,acmorrow/mongo-cxx-driver,xdg/mongo-cxx-driver,mongodb/mongo-cxx-driver,xdg/mongo-cxx-driver,mongodb/mongo-cxx-driver