Switch to case insensitive comparison of HTTP headers

[jonsten]

Fixes #533

A bug was introduced in 67cefb2 where http headers no longer was compared case insensitively. This causes problems for Artifactory instances that run behind proxys that normalizes the http headers.

This change fixes the issue by mimicking the implementation in org.apache.http.message.HeaderGroup by using String#equalsIgnoreCase(). Which is the old and correct behaviour.

I haven't added any tests nor tried to build the code base since Gradle is unable to find some dependencies :(

• All tests passed. If this feature is not already covered by the tests, I added new tests.

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[jonsten]

Looks like we don't have any CLA signed. It will probably take a few weeks/months to get that setup through legal considering that it is vacation time right now...

[yahavi]

@jonsten,
Thanks for your contribution!
Would you like that we will create a separate PR to fix this issue?

[jonsten]

That is fine with me, thanks!

[yahavi]

Thanks, @jonsten. I created #539 to fix this issue.