public Builder proxyConfiguration(final HttpProxyConfiguration proxyConfiguration) {
            this.proxyConfiguration = proxyConfiguration;
            return self();
        }
This class is essentially a copy of {@link io.dropwizard.client.HttpClientConfiguration}
so that we can extend {@link AbstractConfig} and have an equals method.
All uses of {@link io.dropwizard.util.Duration} have been replaced with {@link StroomDuration}
for consistency with the rest of the config.
Values are extracted from this using reflection by {@link stroom.util.http.HttpClientConfigConverter} so it is
key that the method names match.
stroom-util/src/main/java/stroom/util/http/HttpClientConfiguration.java