Adding two errors to xio_status

Signed-off-by: Eyal Salomon <esalomon@mellanox.com>
1. server rejection to session results in teardown of connection and session
2. adding connection disconnection notification function

Signed-off-by: Eyal Salomon <esalomon@mellanox.com>
when xio_session_destroy is not called on session teardown callback
the session state is not changed and that causes more then one
"session teardown" notification

Signed-off-by: Eyal Salomon <esalomon@mellanox.com>
introducing 3 new utility functions:

1. xio_get_connection_context - returns connection's associated context
2. xio_set_context_params - allows the user to set specific context parameters
3. xio_get_context_params - allows the user to get assigned parameters

Signed-off-by: Eyal Salomon <esalomon@mellanox.com>