fabfile: install uuid-runtime and python-argparse

Because the are needed to run vstart.sh which is used when running
unittests.

Signed-off-by: Loic Dachary <loic@dachary.org>
Merge pull request #6 from dachary/master

fabfile: install uuid-runtime and python-argparse

Reviewed-by: Sage Weil <sage@inktank.com>