…ackets.

On the client:
* Origin.Address.host is passed through HostPort.normalizeHost(),
so that if it is IPv6 is bracketed.
Now the ipv6 address passed to an `HttClient` request is bracketed.
* HttpRequest was de-bracketing the host, but now it does not anymore.

On the server:
* Request.getLocalAddr(), getLocalName(), getRemoteAddr(),
getRemoteHost(), getServerName(), when dealing with an IPv6 address,
return it bracketed.
The reason to return bracketed IPv6 also from *Addr() methods is that
if it is used with InetAddress/InetSocketAddress it still works, but
often it is interpreted as a URI host so brackets are necessary.
* DoSFilter was blindly bracketing - now it does not.

Added a number of test cases, and fixed those that expected
non-bracketed IPv6.

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>

…ackets.

Fixed Jenkins failures by disabling tests that require IPv6 if it is not available.

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>

…ackets.

Updates after review.

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>

…ackets.

Reverted code changes to HttpClient.normalizeHost().

Signed-off-by: Simone Bordet <simone.bordet@gmail.com>