Osgi-ify hystrix-core, hystrix-examples

Followed Ben's suggestions on how to add osgi manifest to hystrix.  https://github.com/Netflix/Hystrix/issues/309

[CONCERNS]
Some concerns I have is that the hystrix-core/build/libs/hystrix-core...jar doesn't contain the archeaus dependencies.  Is there something I should do to ensure these libs are compiled into the jar?