Support the siteconf feature

Patch to support the siteconf feature, from [w3m-dev 04463]
on 2012-06-27, provided by AIDA Shinra.

display.c

@@ -257,7 +257,7 @@ make_lastline_link(Buffer *buf, char *title, char *url)
     parseURL2(url, &pu, baseURL(buf));
     u = parsedURL2Str(&pu);
     if (DecodeURL)
-	u = Strnew_charp(url_unquote_conv(u->ptr, buf->document_charset));
+	u = Strnew_charp(url_decode2(u->ptr, buf));
 #ifdef USE_M17N
     u = checkType(u, &pr, NULL);
 #endif