Added import of tframe in NAMESPACE.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/tsanalysis@153 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
minor edit.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/tsanalysis@154 edb9625f-4e0d-4859-8d74-9fd3b1da38cb