Before they are used, rename ap_str[n]casecmp() to ap_casecmpstr[n]() to match

what will probably be their APR names, avoiding any confusion wrt <strings.h>'s
functions (semantic).


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1715736 13f79535-47bb-0310-9956-ffa450edef68