fixes gh-685

The aspectjweaver jar includes all of aspectjrt, and the former is
used at runtime in a number of places (tests fail if you remove
it). Both are not needed so we have picked one (the other one than
recommended in gh-666).

Fixes gh-666

fixes gh-591

fixes gh-651

fixes gh-623

fixes gh-635

fixes gh-589

* For Java 8 users, Spectator is the recommended metrics library as Servo is now deprecated in favor of Spectator
* Servo support now needs to be specifically enabled via @EnableServo, even if servo-core is included on the classpath
* Added starter modules for both Spectator and Atlas support
* ServoMetricReader defines a convention for mapping tag-based metrics to hiearchical names for rendering by the Actuator /metrics endpoint

fixes gh-525

Adds support for feign-hystrix

fixes gh-606

fixes gh-600

fixes gh-596

fixes gh-591

fixes gh-527

Eureka now only directly depends on java.inject.

Fixes gh-529

fixes gh-576

Still a release candidate (not yet GA), but seems to work, so we'll
try and update before Spring Cloud is released again.

Fixes gh-546, fixes gh-567, fixes gh-553 (probably)

fixes gh-561

Change EurekaInstanceConfig.getSID to getInstanceId

fixes gh-554

Remove Servo from EurekaHealthIndicator.
Remove custom DataCenterInfo.
EurekaInstanceConfig.SID is now used as eureka id.
EurekaInstanceConfigBean.getSID falls back to metadataMap.instanceId for
backwards compatibility.

fixes gh-534

Move turbine/hystrix amqp specific implementations to spring-cloud-stream based implementations and let the user decide which broker to use.

fixes gh-545

1.4.15 isn't in maven central yet

fixes gh-534

fixes gh-540

Synchronizes on the version in use by Feign.

Closes #4920

fixes gh-479