Update CREDITS.md
Update CREDITS.md

Add authors from GIT commits
git log --format="%aN" 664fdf79c88064fd640ed148e2f5e65ab74e2e7d..HEAD | sort /unique

GerHobbelt/civet-webserver,GerHobbelt/civet-webserver,GerHobbelt/civet-webserver,GerHobbelt/civet-webserver,GerHobbelt/civet-webserver,GerHobbelt/civet-webserver