jax-rs

Hi, I have discovered issue when using feign.httpclient.ApacheHttpClient.
In some cases Apache client throws ProtocolException which is a checked exception. This happens for example when server returned 303 HTTP code but there was no location header.
In such case Feign proxy throws UndeclaredThrowableException instead of invoking ErrorDecoder.

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this specification does not dictate a particular approach at this time, though it does support the use of an “Expires” header 
to limit the time period a file will be available for client download (removal of the file from the ser

opentracing-concurrent is used in tests therefore should be removed from opentracing-jaxrs2