adds a performance method for crossval objects.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/analogue@407 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
two further changes that should have gone with r407; documentation tweaked for performance()

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/analogue@408 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
minor documentation tweak

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/analogue@409 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
ChiSquare function wasn't returning the list it generated

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/analogue@410 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
document r410

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/analogue@411 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
the progressbar was resetting between repeats of k-fold CV

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/analogue@412 edb9625f-4e0d-4859-8d74-9fd3b1da38cb