Refactor SQL Entities - User, FeedbackResponse, FeedbackResponseComment

[domlimm]

• Leverage on Foreign Key / Relations between Entities by a SQL DB for User, FeedbackResponse, FeedbackResponseComment
• Remove Section attributes if a relation is to exist between Entity T and User
• Generics for necessary methods
• Look into possible solutions to be compatible and scalable with existing NoSQL *Data files
• Update all affected methods / tests based
• Complete migration for updateStudentCascade
• Update ERD