kiji-schema: SCHEMA-674. Update DebugResourceTracker LOG messages

issue: https://jira.kiji.org/browse/SCHEMA-674
review: https://review.kiji.org/r/1732
over-the-shoulder-reviewers: daisy
commit: https://github.com/kijiproject/kiji-schema/commit/e9b7404219e1e68d5bd3d731c815967093b45bbb