upgraded to release 0.5.549.1.0 with test release 5.549.1alpha of Armadillo
revert back to previous mul_gemm.hpp
release 0.4.549.2.0 with test release 4.549.2alpha of Armadillo: updated mul_gemm.hpp
actually setting DESCRIPTION version
Merge pull request #27 from RcppCore/feature/arma-4.549alpha

Feature/arma 4.549alpha