Handle stream error early

Handle stream error early

Should fix inconsistent logging due to Reactor Signal sometimes
propagating from WireChunkDecoder stream to VesHvCollector stream as
Signal.CANCEL instead of Signal.ERROR and thus not being handled
correctly.
As a drawback however we will log error twice in case it comes from
WireChunkDecoder as we want to terminate connection in such case and
so we need to propagate error.

In WireChunkDecoder `doOnTerminate` was changed to
`doFinally` as this method handles also cancellation
signals and not only terminal signals.

Also fixed minor checkstyle reported issues.

Change-Id: I6e91d96c5a1a3ecf30603db9a71e032c770d507f
Issue-ID: DCAEGEN2-955
Signed-off-by: Filip Krzywka <filip.krzywka@nokia.com>