Reduced dependency on magic number status codes in server core

and removed artificial restrictions on range of codes used by server,
particularly in mod_asis where flexibility is paramount.
Many other modules continue to use magic numbers, but those can wait.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@76880 13f79535-47bb-0310-9956-ffa450edef68