add Derik Lu to contributors.
add Derik Lu to contributors.

lauratavares/first-contributions,Abhishekchakru/first-contributions,FearTheFrail/first-contributions,Abhishekchakru/first-contributions,lauratavares/first-contributions,FearTheFrail/first-contributions,RickHaan/first-contributions,RickHaan/first-contributions