Show cluster name in status command.
Semi
Merge pull request #168 from aholmberg/status-report-cluster

Show cluster name in status command.
Add yaml_merge function to common.py
Add argument to pass in yaml file to updateconf
Merge custom yaml into each node's cassandra.yaml
Validate yaml_file path exists
Add test for yaml_merge
Improve yaml_merge

Was unnecessarily complex. Was not merging items that were in
primary but not in secondary
Merge pull request #172 from pcmanus/updateconf_yaml

Updateconf yaml
Do not add yaml_file to cassandra.yaml
Remove --yaml from updateconf
Allow for specification of subfields in nested yaml blocks
Do not coerce False or True to integers
Handle yaml entry not existing

The isinstance(x, dict) check throws a KeyError if the
new property is not already in cassandra.yaml.
Use psutil for pid tracking on windows
Update README for psutil dependency
Move psutil import in-line.

Now the dependency change will only be forced for users on Windows.
This will prevent Linux users from discovering a new dependency
has been added.
Remove yaml_merge test
If psutil not installed, gracefully fall back to old behavior