Implement composite interest index as an aggregate of atomic indexes.
Use Ribbon transport in eureka-client.
Merge tbak/2.x with netflix/2.x

Conflicts:
	eureka-core/src/main/java/com/netflix/eureka/interests/IndexRegistry.java
Increase timeouts in test.
Reimplement InterestNotificationMultiplexer to be thread safe.
Fix InterestNotificationMultiplexer implementation.
Yet another InterestNotificationMultiplexer implementation.
Minor server resolver update.
Get rid of easymock (use mockito instead).
Merge pull request #197 from tbak/2.x

2.x composite interest index + ribbon in eureka-client + a few other updates