Clean up syntax highlighting styles in CodeWorld editor
Clean up syntax highlighting styles in CodeWorld editor

Fixes #117

tgdavies/codeworld,parvmor/codeworld,alphalambda/codeworld,three/codeworld,stefan-j/codeworld,google/codeworld,venkat24/codeworld,tgdavies/codeworld,three/codeworld,venkat24/codeworld,venkat24/codeworld,pranjaltale16/codeworld,pranjaltale16/codeworld,parvmor/codeworld,nomeata/codeworld,stefan-j/codeworld,nomeata/codeworld,stefan-j/codeworld,alphalambda/codeworld,alphalambda/codeworld,tgdavies/codeworld,nomeata/codeworld,parvmor/codeworld,pranjaltale16/codeworld,google/codeworld,google/codeworld,three/codeworld