awsutils: fix custom block device mapping bug

Turns out HVM instances require the ephemeral drives to be mapped to
/dev/sdX instead of /dev/sdX1, otherwise instances fail to launch with a
Server.InternalError.

closes gh-213
closes gh-46
setup: bump dependencies to latest versions
tests: pep8/pyflakes clean-up
More debug info
Merge branch 'develop' of git://github.com/jtriley/StarCluster into datacratic_dev