small refactoring
add: TODO
progress: Failed 18 :(
progress: Failed 10

directory index file exists ... FAIL
document root escaping forbidden ... FAIL
urlencoded filename ... FAIL
query string after filename ... FAIL
filename with spaces ... FAIL
Content-Type for .html ... FAIL
head method support ... FAIL
directory index file absent ... FAIL
post method forbidden ... FAIL
Server header exists ... FAIL