Adding auth headers to eureka client and server outbound requests.
Adding filter to optionally log auth headers in eureka server.
Renaming of classes and filters for more clarity
Removing config for identity header filters.
Changing default config for server identity logging to true.
Merge pull request #142 from qiangdavidliu/add-auth-headers

Adding auth headers
[Gradle Release Plugin] - pre tag commit:  '1.1.136'.
[Gradle Release Plugin] - new version commit:  '1.1.137-SNAPSHOT'.