modify dropbox install doc, root permisison
Merge pull request #2 from qingpeng/fix/dropbox

modify dropbox install doc, root permisison
Merge pull request #9 from qingpeng/2014

add tutorial about amazon instance file transfer, EBS volumn
update ints
Merge branch '2014' of https://github.com/ngs-docs/angus into 2014
add missing figure