keyframes can now be directly specified in MGC_Linear constructor.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/clusterds@240 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
added some files.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/clusterds@241 edb9625f-4e0d-4859-8d74-9fd3b1da38cb