Support for from-timestamp message consumption

[pierre-degrandmaison]

Converting timestamp to topic/partition offset is not easy without coding.... a nice new feature would be to be able to consume messages by providing from-timestamp, and let the kafkactl code compute the corresponding start offset value.

[d-rk]

Hey @pierre-degrandmaison
I already thought about this and implementing it would be not that complicated.

In this method one could determine the start offset with:

oldestOffset, err = (*client).GetOffset(topic, partition, fromTS)

So if you are willing to work on it, a PR is always welcome 😃

Cheers

[nanic]

Hi @d-rk, Please let me know if you think the changes are enough and if i am missing anything. I did notice the timeout issue referred in #67 .

[pierre-degrandmaison]

Works great! very useful, thank you