Log Message:
Update R to 1.9.1

CHANGES IN R VERSION 1.9.1

NEW FEATURES

    o   as.Date() now has a method for "POSIXlt" objects.

    o   mean() has a method for "difftime" objects and so summary()
        works for such objects.

    o   legend() has a new argument 'pt.cex'.

    o   plot.ts() has more arguments, particularly 'yax.flip'.

    o   heatmap() has a new 'keep.dendro' argument.

    o   The default barplot method now handles vectors and 1-d arrays
        (e.g., obtained by table()) the same, and uses grey instead of
        heat color palettes in these cases.  (Also fixes PR#6776.)

    o   nls() now looks for variables and functions in its formula in
        the environment of the formula before the search path, in the
        same way lm() etc look for variables in their formulae.

DEPRECATED & DEFUNCT

    o   Support for non-IEEE-754 arithmetic (which has been untested
        for some time) will be removed in the next full release.

    o   Direct use of R INSTALL|REMOVE|BATCH|COMPILE|SHLIB is
        deprecated: use R CMD instead.

    o   The gnome/GNOME graphics device is deprecated and will be
        removed in the next full release.

Plus Bug Fixes.