Add test to test future returned from withMeta() API. Remove HttpClient from the public constructor of HttpRequestTemplate.
Fix the problem that max response timeout is not set correctly with Hystrix. Make RequestTemplate an abstract class to facilitate future additions.
Move withFallbackHandler implementation to RequestTemplate.
Make RequestTemplate an abstract class. Added test to make sure ClientOptions and Hystrix properties set correctly. Fix the problem that DefaultClientConfigImpl.getPropertyWithType() does not honor archaius property.
Merge pull request #108 from allenxwang/2.x-commonclient

Change RequestTemplate to abstract class and some bug fixes
Merge remote-tracking branch 'netflix/2.x-commonclient' into 2.x-commonclient