finishHandshake() always starts new thread for each request

At time of completion of an ssl handshake TransportContext.finishHandshake() always starts a new thread to finish the ssl handshake.

Creating a new Thread every time to complete the handshake create problem if you open lot's of SSL connections.

We encounters native OOM due to thread leak, there are some 8000 threads of type "HandshakeCompletedNotify-Thread".

We should consider of using the Thread pool instead of creating a new Thread every time.