merge from git

git-svn-id: https://hedgehog.fhcrc.org/bioconductor/trunk/madman/Rpacks/flowWorkspace@85748 bc3139a8-67e5-0310-9ffc-ced21a209358
Merge commit '1148624665bc99802246974b0e429e538233cc62' into trunk
fix bug in getSampleGroups method.