Fix up the wording, so it leaves no doubt that status codes outside the...

Fix up the wording, so it leaves no doubt that status codes outside the 300-399 range are also perfectly fine.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1346290 13f79535-47bb-0310-9956-ffa450edef68