Additional Context Options for https, Restore Disabled Tests

[oleibman]

Additional Context Options needed, at least sometimes, to read https images.

This is:

• a bugfix
• a new feature
• refactoring
• additional unit tests

Checklist:

• Changes are covered by unit tests
  • Changes are covered by existing unit tests
  • New unit tests have been added
• Code style is respected
• Commit message explains why the change is made (see https://github.com/erlang/otp/wiki/Writing-good-commit-messages)
• CHANGELOG.md contains a short summary of the change and a link to the pull request if applicable
• Documentation is updated as necessary

Why this change is needed?

Provide an explanation of why this change is needed, with links to any Issues (if appropriate).
If this is a bugfix or a new feature, and there are no existing Issues, then please also create an issue that will make it easier to track progress with this PR.

[oleibman]

No idea what Scrutinizer's problem is today.

[lucasnetau]

It's the keep-alive causing the 2m timeout. Try Connection:close instead, keep-alive isn't always required it's just what a browser would do.

I'd also recommend setting timeout setting for the http context to a lower value of say 10sec depending on your needs.