added help to msnbase.r

git-svn-id: https://hedgehog.fhcrc.org/bioconductor/trunk/madman/Rpacks/MSnbase@72370 bc3139a8-67e5-0310-9ffc-ced21a209358
NEWS/DESCRIPTION update

git-svn-id: https://hedgehog.fhcrc.org/bioconductor/trunk/madman/Rpacks/MSnbase@72371 bc3139a8-67e5-0310-9ffc-ced21a209358
Merge branch 'local-hedgehog'