Write unit tests for testing nested directory settings in etcd

PIVOTAL_TRACKER_STORY_URL=https://www.pivotaltracker.com/story/show/82827552
PIVOTAL_TRACKER_STORY_TYPE=feature
PIVOTAL_TRACKER_STORY_ESTIMATE=5
PIVOTAL_TRACKER_STORY_OWNER=karldominguez
PIVOTAL_TRACKER_STORY_REQUESTER=katdecastro
PIVOTAL_TRACKER_STORY_LABELS=envetcd, soaf