Add an entry to Users.md for CodeDay.
Add an entry to Users.md for CodeDay.

Information is based on an email to codeworld-users by Brendan.
tgdavies/codeworld,parvmor/codeworld,pranjaltale16/codeworld,pranjaltale16/codeworld,three/codeworld,alphalambda/codeworld,nomeata/codeworld,alphalambda/codeworld,parvmor/codeworld,tgdavies/codeworld,parvmor/codeworld,venkat24/codeworld,three/codeworld,venkat24/codeworld,venkat24/codeworld,nomeata/codeworld,tgdavies/codeworld,google/codeworld,google/codeworld,google/codeworld,pranjaltale16/codeworld,nomeata/codeworld,three/codeworld,alphalambda/codeworld