Cloudstack Plugin working against 3.1m5

Hey Guys!

Opening this pull for tracking purposes. Not squashed so with all lousy intermediate commits :)
At this stage it's working on 3.1m5.

But since we are waiting for some commits to be upstreamed on libcloud:
https://github.com/apache/libcloud/pull/371
https://github.com/apache/libcloud/pull/369

It depends on our forked branch for now:
https://github.com/schubergphilis/libcloud/tree/pending

Mini howto here: https://github.com/schubergphilis/cloudify-cloudstack-plugin/blob/3.1m5/README.md

At the moment,  we install this branch after deployment init,  in the virtualenv of the deployment on the manager.
There must be a smarter way, but did it for now.

A review would be appreciated, factor in that we are not your average hardcore python programmer :), nonetheless feedback appreciated.

VPC support is in here as well, but not tested yet on this commit. 

Todo (not exhaustive):
- Validate VPC support after last refactor
- blueprint with VPC networking for manager and node cellar
- Plugin Documentation
- key pair magic
- get plugin template inline with rc1
- more functionality such as data disks, snapshots
- code review / optimisation
- tests tests test