Configuration files are text files so open them in text mode.

Some OS/2 (and probably DOS & Windows) text editors like to put Ctrl-Z EOF
markers at the end of the files they edit. Opening the config files in text
mode prevents the Ctrl-Z from causing 'Invalid command' errors when starting.

PR: 4632


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@83905 13f79535-47bb-0310-9956-ffa450edef68