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

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.