Make man page lookup case-insensitive.
 [rsc] --rw-rw-r-- M 771144 glenda sys 9069 Feb 11 09:15 sys/src/cmd/ip/httpd/man2html.c
	/n/sourcesdump/2006/0211/plan9/sys/src/cmd/ip/httpd/man2html.c:162,167 - 
	/n/sourcesdump/2006/0212/plan9/sys/src/cmd/ip/httpd/man2html.c:162,175
	  }
	  
	  void
	+ strlwr(char *p)
	+ {
	+ 	for(; *p; p++)
	+ 		if('A' <= *p && *p <= 'Z')
	+ 			*p += 'a'-'A';
	+ }
	+ 
	+ void
	  redirectto(char *uri)
	  {
	  	if(connect){
	/n/sourcesdump/2006/0211/plan9/sys/src/cmd/ip/httpd/man2html.c:313,323 - 
	/n/sourcesdump/2006/0212/plan9/sys/src/cmd/ip/httpd/man2html.c:321,340
	  	p = strstr(uri, "/intro");
	  
	  	if(p == nil){
	+ 		while(*uri == '/')
	+ 			uri++;
	  		/* redirect section requests */
	  		snprint(file, sizeof(file), "/sys/man/%s", uri);
	  		d = dirstat(file);
	- 		if(d == nil)
	+ 		if(d == nil){
	+ 			strlwr(file);
	+ 			if(dirstat(file) != nil){
	+ 				snprint(file, sizeof(file), "/magic/man2html/%s", uri);
	+ 				strlwr(file);
	+ 				redirectto(file);
	+ 			}
	  			error(uri, "man page not found");
	+ 		}
	  		x = d->qid.type;
	  		free(d);
	  		if(x & QTDIR){