0.2    first version to CRAN
 0.2-1  fixed bugs in docs found by scripts on CRAN (R-devel check)
 0.3    added data/echinacea.txt
              man/echinacea.Rd
              test/tutor.R
        added test in aster.R
        added package vignette
        added examples on all help pages to be used by users