Add more windows series

* Add windows 7, 8 and 8.1 to supported series
* get windows product name from registry instead of powershell commandlet
move test setup into setup/teardown phase
wip
Merge branch 'master' of https://github.com/juju/juju into 119-version-tests
Modified config file to create all-machines.log with 0600 permissions.
juju/testing: do not tear down connection if setup fails
More fixes
Merge pull request #232 from katco-/b1286518-log-perms

Modified config file to create all-machines.log with 0600 permissions.

https://bugs.launchpad.net/juju-core/+bug/1286518
responding to review feedback
Merge pull request #233 from davecheney/126-do-not-close-state-and-apiserver-connections-if-setup-fails

juju/testing: do not tear down connection if setup fails

Our test suite helpers are a double edged sword. They tend to expect the best, and blow up when the worst happens. This change is an example of this, if the setup phase failed, then what was a c.Assert("couldn't talk to mongo") becomes a panic when the tear down phase tries to close a connection which was never opened.
Merge branch 'master' of https://github.com/juju/juju into 119-version-tests
Responding to review feedback
Merge pull request #229 from davecheney/119-version-tests

version: add more unit tests
API server is now dual stack capable, listening on both
IPv4 and IPv6 endpoints.
Merge pull request #224 from dimitern/apiserver-listens-dualstack

state/apiserver: Ensure we always listen to IPv4+IPv6

API server is now dual stack (IPv4+IPv6) capable, as it
listens on both 127.0.0.1 and ::1, and clients can connect
to it using both protocols. Added tests and some internal
details needed tweaking. Live tested on EC2.
Merge pull request #179 from gabriel-samfira/add-more-windows-series

Add more windows series

* Add windows 7, 8 and 8.1 to supported series
* get windows product name from registry
fix NetworkInterface.SetDisabled
Merge pull request #237 from klyachin/125-setdisabled

Fix NetworkInterface.SetDisabled

I have fixed NetworkInterface.SetDisabled(flag) method to modify doc immediately as the disable state has been changed.