INT-2956 Fix NIO With Custom Deserializers

The TcpNioConnection uses an internal InputStream.

The standard deserializers only use the read() method.

Custom Deserializers might use read(byte[]); the
internal InputStream did not override these methods, possibly
causing the deserializer to hang awaiting data, when none
was coming.

Override these methods, with the appropriate semantics
from the super class...

- Block until at least one byte arrives.
- Return early if no data is available after at least one byte arrives.
- Return -1 if closed when no data arrived.
- Return the number of bytes actually read.