Merge pull request #204 from zacharylwy/master

Update DG Diagram

Merge pull request #120 from EthanWong6362/master

last minutes changes for demo

Merge pull request #119 from ngjiayuan/sample-data

Add more sample persons

Merge pull request #110 from EthanWong6362/updates-before-demo

Update things before the demo

Merge pull request #99 from aakanshanarain/fix-main-class-issue

Change mainClassName to run the app

Merge pull request #67 from ngjiayuan/fix-create-user

Fix a create command bug