Support matching against multiple header values in HeaderAssertions

[Adamovskiy]

The only way to validate multiple response header values – is to assert for strict equality with valueEquals(String headerName, String... values). Got to be a way to also validate them against regular expression, and with any custom check, like in value(String name, Consumer<String> consumer) (which btw has wrong copy-pasted javadoc).

Other method javadocs say that they work with "primary value". There is no such term neither in RFC7230, nor in RFC6265. It seems that all values should be treated as equally significant.

This functionality is extremely important for work with response cookies (Set-Cookie header).

[sbrannen]

Thanks for raising the issue.

I improved the Javadoc in 46329d0.