Fix bug #994 - manualAcks for QoS 2 messages

[lacourte]

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This patch fixes bug #994.
The fix only concerns the client v5. The bug actually does not exist in the client v3.
The fix reports the implementation of the feature from the client v3 into the client v5.

[whizyrel]

Hello guys, great job here but this issue is still persistent with v5 1.2.5.
I have read #994, and #1023, it does not happen to have a fix.
I have submitted this issue #1054.

[whizyrel]

Hello guys, great job here but this issue is still persistent with v5 1.2.5.
I have read #994, and #1023, it does not happen to have a fix.
I have submitted this issue #1054.