1. Added methods to not ask for the Database instance for retrieving database records
2. Modified getRootFolder to set the parent id to the system folder id (1)
3. Removed validation for positive id for deleting study
4. Modified existing JUnit tests and added new JUnit tests for the revised logic for Nurseries/Trials/Studies to display per program unique id

Reviewer: Crisjaira Villarino (post-commit)

BMS-216