Patch for http to https proxy

[sukrit007]

Set agent for proxy to address connection refused for proxying request from http to https.

See: https://github.com/nodejitsu/node-http-proxy/blob/caronte/examples/http/proxy-http-to-https.js

It also requires setting of host headers but that can be passed using proxy config.

Purpose of the agent property and PR:
Basically I am running into issue where in if I have http frontend with https proxy backend, I get "Connection Refused". FOr reference here is the issue :
http-party/node-http-proxy#304

To address this issue, we need to do 2 things:

Pass the host header
Pass the agent property

The PR adds the ability to add the agent property to support https proxy to BE host for http front end. In addition it adds the ability to override host header.

[io41]

Isn't this covered by PR #101 ? (which also as improved default port handling and fixed usage of the proxy api)

[ruiaraujo]

I am not really sure the title for this PR is correct.
@sukrit007 What is the goal of that agent property?

[sukrit007]

@ruiaraujo Looks like there are some conflicts now. I will rebase my changes and squash commits.

Purpose of the agent property and PR:
Basically I am running into issue where in if I have http frontend with https proxy backend, I get "Connection Refused". FOr reference here is the issue :
http-party/node-http-proxy#304

To address this issue, we need to do 2 things:

• Pass the host header
• Pass the agent property

I could do first one by passing explicit headers, but could not set the agent property.

[sukrit007]

@io41 I looked at the PR but did not see agent property. I will rebase my changes and pass the agent property. I need agent property to address http to https proxy (See explanation above)

[sukrit007]

@ruiaraujo : Ready for review

Changes:

• re-based my changes. ( also squashed commits)
• resolved merge conflicts
• Added ability to override host header

[sukrit007]

Just wanted to followup on this PR. Do you need anything else wrt same ?

[cosmin-dumitrache]

@ruiaraujo Hi, can you please merge this? I've ran into this issue with my setup as well and this pull request fixed it.

EDIT: Actually, I am seeing an issue. It works when testing with postman, but Chrome and Safari give an error saying the content can not be decoded.

[sukrit007]

@cosmin-dumitrache working fine on Chrome/Safari. Can you provide exact steps.

Also I will rebase the changes to resolve conflicts. @ruiaraujo: Would you need me to address anything else in this PR ?