Upgrade pip to 1.3.1

This provides pip list --outdated that allows us to see which packages
are out of date.
Upgrade python packages

argh pymongo nose requests pep8 python-dateutil pytz
Remove creation of virtualenv

This forces the pip version back to default which in turn forces it to
be reinstalled when depdendencies are installed.
Add script to check python package version

Send me an email if my outdated packages is different to last time you
ran.