use package "tools" version of assertError() and assertWarning()

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/matrix@2968 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
loosen one check for openBLAS

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/matrix@2969 edb9625f-4e0d-4859-8d74-9fd3b1da38cb