auth: Add :netrc | {:netrc, path} as possible values

[wojtekmach]

Instead of having a distinct load_netrc step, make it an option to auth, e.g.: auth: :netrc which also would be the default?

[wojtekmach]

Let's still keep it as a distinct step, it's just auth/2 is going to use it under the hood.

[srowley]

Looking at this, I am not sure why keeping load_netrc as a step is desirable. Could you confirm?

If you run both steps, it will send two authorization headers, which I believe is not consistent with RFC7230.

It makes sense to me to keep load_netrc only as a private function to run under the hood - maybe this was the intent?

[srowley]

Separate question - load_netrc seems to be looking for a file with lines like:

machine localhost
username foo
password bar

But the documentation I can find here and here suggests it should be:

machine localhost
login foo
password bar

or

machine localhost login foo password bar

Should I stick with username or use login?

[wojtekmach]

oops, it should have been login, thanks!