Add documentation
Add health ID encryption backfill
Merge remote-tracking branch 'base/develop' into develop
Refactor distributed lock
Merge remote-tracking branch 'base/develop' into develop
Remove user lock DAO
Add RedisDistributedLockDaoTest
Rename methods
Remove unused field
Fix test failures
More aggressive precondition checks
Fix a nasty bug that some test user accounts are missing health code
Add skeleton backfill test
Refactor with method name changes
Changes per code review
Merge remote-tracking branch 'base/develop' into develop

Conflicts:
	app/org/sagebionetworks/bridge/services/StudyServiceImpl.java
Merge pull request #354 from eric-wu/develop

backfill health code encryption GCM mode; fix dangling health code mappings for test users; refactor lock dao