Release of 1.4.16

- a3d77f42f694896c663ea4063a6aa15a8b014302: Merge pull request #917 from mattrjacobs/remove-intermediate-servo-command-class
- cd2f1fee8380abacac36906e1e6a3474abcca886: Better implementation that allows overriding classes of HystrixServoMetricsPublisherCommand to be less-aware of implementation details
- dfdecf5b06eb6ecf1a6dc6798a41c4e05ee9140c: Merge pull request #912 from mattrjacobs/only-check-cache-enabled-once-observable-collapser
- 46cc7b0321d1fd8abde9d274d8d991b0ef9b84d9: Only check the property value of isRequestCacheEnabled() once in HystrixObservableCollapser
- 29518d6a5deefeb7e4a73c35fb3c3f96278b4087: Merge pull request #911 from mattrjacobs/queue-saturation
- dd0dc3458310eb02a8ff788396c2a3dbfdbd04e6: Merge pull request #910 from mattrjacobs/servo-metrics-abstraction
- b85156d058ce193a7d5b6c5c2f30cb49142beab5: Added the queue() case to large threadpool/small queue testcase
- 6920a53d97574996b09e0c8e9e5ec4db28b16485: Added unit test to see what happens when a large pool with a small queue sees high concurrency
- a97cc6a89603cea093eb5ccaabbdde6f1b6b8434: Fixing license date
- c9a40f17734cec44a25702ab7a7b7d761427b775: Adding a layer of abstraction to Servo integration for Hystrix command metrics that doesn't assume a specific implementation
- a8b064d9ad95513c16163f9f5e09c9a76b7e0dff: Merge pull request #905 from ruhkopf/1.4.x_ObservableCollapser_example
- 1c1cfd332ca47bdbbf64721d9d0e25200213c4f8: add java 8 examples as comment
- 0d3d18039110620b8b751d7ab4f98e3b0147073a: Added example demonstrating ObservableCollapser
- 881a4c9de60256a517318302ca64b9549366937e: Merge pull request #902 from mattrjacobs/request-context-for-hystrix-observable-collapser
- 93858397373691853ee3cc26efb2306712fce267: Moving the subscribe() to before the await in HystrixObservableCollapserTest
- a2fc37986216e3c3d1bad9069ac188253832ed94: Update unit tests for HystrixObservableCollapser to check HystrixRequestContext
- 5affd5c9ff1d1ad56e27b917fbce686a9d38b8ba: Merge pull request #900 from mattrjacobs/backport-899
- 0f5034aa40fa7159b7478dda6720d90879780868: Remove commons-collections dependency.
- c16318bc5e9719e049b005aca04946c08c2da7d1: Merge pull request #897 from mattrjacobs/backport-896
- 400bf5aa69c7714ea0dddf0bf3d2c10a5a803008: Fix missing null check in HystrixCacheKeyGenerator.
