- fix config.m4 (CURL_LIBS define was missing)

- fix HAVE_LIBMHASH -> HTTP_HAVE_MHASH macro
- check for curl_*_strerror() in the lib and assume they're there for windows
- separate http_request_method_api (should be available even without libcurl)
- use custom displayer for http.etag_mode INI entry
- simplify phpinfo() output