Proxy authentication does not work for HTTPS.

[vasiliyl]

When connecting to HTTPS via proxy Proxy-Authorization header is not sent.
Proxy authentication for HTTPS should work the same way as for HTTP.

I'm behind the proxy with authentication right now, https_proxy environment variable is set to http://user:pass@proxy:3128, and here is what I get with stack:

$ stack build        
Downloading nightly-2015-06-12 build plan ...ProxyConnectException "raw.githubusercontent.com" 443 (Left "StatusHeaders (Status {statusCode = 407, statusMessage = \"Proxy Authentication Required\"}) <...some more headers...>

Here is dump of stack's request:

CONNECT raw.githubusercontent.com:443 HTTP/1.1

Here is dump of request done with curl which works fine:

CONNECT raw.githubusercontent.com:443 HTTP/1.1\r\n
Host: raw.githubusercontent.com:443\r\n
Proxy-Authorization: Basic dXNlcjpwYXNz\r\n
User-Agent: curl/7.42.1\r\n
Proxy-Connection: Keep-Alive\r\n

[snoyberg]

I'm not well set up to test this. Would you be able to take a stab at this? The change should be pretty trivial, just modify the CONNECT call in Network.HTTP.Client.Manager to respect the proxy-authentication header in requestHeaders.

[vasiliyl]

I created merge request #133, it works for me. The code is trivial, but I'm new to haskell, please comment if there is a better solution.

[snoyberg]

Merged to master, closing as resolved. If there are still issues, please report. Thanks for the PR!