Kevin Roth's patch that checks for the CA cert file at two more places if the

--cacert option is not used.

1. An environment variable named CURL_CA_BUNDLE may contain the full file
name to the file.

2. On Windows, the cert file may be named curl-ca-bundle.crt and put in the
same dir as curl is located (or the CWD) and curl will then use that file
instead.