Fix PD not scaling down when waiting processes are terminated.

Also add a corresponding test
Modify needy engine to prioritize removing the freshest VM on downscale
Remove stray prints
pep8 tidy
Make PD request retirable nodes with the newest first
Revert "Modify needy engine to prioritize removing the freshest VM on downscale"

This reverts commit ef94ad36fd86ff090934b305415d07063dc99454.

Conflicts:
	epu/decisionengine/impls/needy.py
Fix gevent config for ZooKeeper store classes
Be more cautious when initializing HA policy
pep8 tidy
Add tests to expose provisioner terminate_all bug
Fix provisioner ZK connection handling/recovery
Fix typo in filename
pep8 fixes
Remove vagrant provisioner
More cautious testing in test_terminate_when_waiting
Update requirements.txt to use the new dashi version
Merge branch 'master' into phantom0.2