1. encode the flags as json
2. pass node_id, bus_id rather than DseNode instance.
Create DseNode in harness not eventlet_server.
Rationale: global_conf not meant to take non-strings.
Somehow got away with it in python2, but fails in python3.
When dict (and DseNode) passed through global_conf,
paste.deploy.loadapp adds them to configparser defaults,
causing errors when configparser calls string methods on them.
File "/usr/lib/python3.4/configparser.py",
line 390, in _interpolate_some
p = rest.find("%")
AttributeError:
Error in file congress/tests/etc/api-paste.ini:
'dict' object has no attribute 'find'
Change-Id: I549b9281e72512bb804a7d6f07bf6482e9485ae4
7c6d7c5ad2