Fix Issue #61

add hook for custom ssl factory and AcceptAllSocketFactory implementation

Make sure NamedConnectionPool instances register with Servo with unique names.

Fix RestClient connection leaks when it throws ClientException upon server throttle. Enhanced JUnit tests for RestClient retries.

Fix RestClient connection leaks when it throws ClientException upon server throttle. Enhanced JUnit tests for RestClient retries.

Upgrade httpasyncclient version to 4.0 GA. Added concurrency and read timeout tests.

In JUnit, make sure connection pool size is equal to concurrency level to avoid timeout from connection pool.

Add async HTTP support based on Apache's HttpAsyncClient

Add internal buffering to any unconsumed data by the decoder so that decoder does not need to repeat the boilerplate code to buffer unconsumed data. Changing the JUnit tests and examples correspondingly.

Add more locks to AsyncBackupRequestExecutor to make it run consistently across implementations.

Clean up compiler warnings. Remove dependency on jersey-bundle and add dependency on jersey-client and separate jars.

Remove check style. Make connection pool test in separate test and use a unique client name to avoid reusing the same client in another test.