merge from git

git-svn-id: https://hedgehog.fhcrc.org/bioconductor/trunk/madman/Rpacks/flowCore@83412 bc3139a8-67e5-0310-9ffc-ced21a209358
mv vignettes to vignettes folder
Merge commit '7de8a9a275708909f7fec72673f60b66c79b18ab' into trunk
close #19
Merge branch 'trunk' of github.com:RGLab/flowCore into trunk