Move ZvmNode from common to configparser
Clean up `json` module imports
ClusterConfigParser: clean up node collections

Both a list and a dict of the nodes were being maintained. This is
unnecessary.
ZvmNode: refactor _create_node

Instead of the standalone util function, _create_node is now a
classmethod of ZvmNode called `fromdict`.
proxyquery: remove commented-out code
proxyquery: add docstring to _make_exec_requests

It's a simple docstring; it just specifies the expected inputs and
outputs.
Merge pull request #166 from larsbutler/cleanup-ClusterConfigParser

Clean up ClusterConfigParser
proxyquery: factor source header processing

This block is now in a separate function, in order to reduce the overall
size and complexity of `post_job`.
proxyquery: rename cluster config loading funcs
proxyquery: simplify and refactor post_job
Move a ClusterConfigParser method to ZvmNode

`get_list_of_remote_objects` operates only on a ZvmNode, and it seems
more appropriate to just make it an instance method of ZvmNode.
proxyquery: encapsulate cluster config parsing
proxyquery: remove a redundant variable
configparser: fix a pep8 error
proxyquery: add comments to the code

Because there aren't very many.
requirements.txt: fix swift pkg search page

Something changed with the Swift release on Launchpad, so you no longer
find a >=2.0.0 package on launchpad.net/swift.

This was causing package installs to fail.
Merge pull request #167 from larsbutler/cluster-controller-refactoring

ClusterController refactoring
vagrant: switch from keystone to swauth

We use swauth for our Zebra ZeroCloud deployment, so this brings the dev
environment closer to our canonical production configuration.

I also managed to figure out how to do all of the swift configuration
changes during ./stack.sh, so no devstack restart is required before
everything works--just run `vagrant up` and you're ready to go.
Merge pull request #168 from larsbutler/vagrant-swauth

vagrant: switch from keystone to swauth
vagrent: fix numbering in README

To avoid breaking the list numbering, the paragraph must be indented.