Negative acknowledgment not working anymore when value is set to 0

[Chr3is]

Version: 2.8.4

Describe the bug

With following commit: a1a5d48#diff-49bc63455f16e2f0b1fe17ed1ec885135d494883d5a21a3da53d031098d09a33R2485
the behavior how the nack in the listener container is handled was changed. Allowed values for nack are >=0. However when setting the value to 0 you will end in an endless partition reseeking because the new introduced method pauseForNackSleep checks the nack value against > 0 and NOT against >= 0. Due to this behavior the nack value is never reset to -1.

To Reproduce
execute acknowledgment.nack(0);

Expected behavior
When setting the value to 0 an endless partition reseeking does not happen.