Support for custom headers downloading files

[patrickmaurer]

Changes made by @ewilde taken from chocolatey-archive/chocolatey/pull/171

[ferventcoder]

Hi @patrickmaurer - can you please review our CONTRIBUTING.md document and adjust this PR for the changes you will need to make to the commit message (including filing an issue in this code base so you can reference it in your commit), signing the CLA and other such items? Thanks!

[ferventcoder]

The code itself looks fine.

[ferventcoder]

@patrickmaurer have you had an opportunity to review my feedback and respond?

[patrickmaurer]

Well the CLA thing frightened my a bit because of

1. the code isn't mine but from @ewilde (Support for custom headers downloading files chocolatey-archive/chocolatey#171)
2. the CLA legalese itself didn't make me feel very comfortable, I also don't like to disclose all my personal details

[ferventcoder]

That's fair - I don't share CLA details with anyone. Unless litigation comes up, then I would share those details, but only selectively. That's an extreme, I don't expect anything of the sort.

Perhaps @ewilde could provide the PR instead? :/

[ewilde]

@ferventcoder yep happy to do that. Will review the contributing.md and create a new PR

[ferventcoder]

Closed via #329