Detect peer closure and close own socket.

[s-takeuchi]

Add capability to the sender that detects receiver's closure and close own socket automatically.
Add capability to the receiver that detects sender's closure and close own socket automatically.

This ticket is associating to the old trac ticket of 101.
{Detection of connection cut off regarding sender and receiver elements. IF sender element cuts off the connection, receiver needs to detect the connection off. IF receiver element cuts off the connection, sender needs to detect the connection off.}