New --auth-type NTLM per https://github.com/jkbr/httpie/issues/76

New --auth-type NTLM per https://github.com/jkbr/httpie/issues/76

This does authentication with the end server. It doesn't help if you want to NTLM-authenticate with the proxy, which is separate issue https://github.com/jkbr/httpie/issues/159