INT-1956 TCP: Emit Stream Decoding Events

JIRA: https://jira.spring.io/browse/INT-1956

Emit an application event when a decoding exception
occurs, allowing the user to examine the buffer
at the time the exception occurred.

INT-1956: Polishing

Polishing

Use `OP_READ` instead of `readyOps()` when removing interest.

Polishing - Fix ConnectionTimeoutTests

Test publisher was casting all events to TcpConnectionEvent.