DESCRIPTION: corrected a typo in (biocView -> biocViews)

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>
NAMESPACE: cleaned imports/exports

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>
vignettes/MetaMinerR.Rmd: forgot to add the changes from the example of the alternative way to create a design data.frame

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>