Increase buffer size when discovering objects

[rjseibert]

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What

The discover functionality was noting queues as usage="NORMAL" even when it was verified on the queue manager that usage="XMITQ". There was a startup error message noted in #161.

How

I increased the buffer size when searching for MQ objects on a queue manager.

Testing

I have run unit tests. I also have this changed code connecting to a queue manager with 10,000+ queues (mostly cluster queues).

Issues

Resolves #161 .

[ibmmqmet]

The latest version has what I hope to be a better solution to this problem, rather than simply increasing the buffer size. As well as truncation I suspected that we might have been finding a non-data reply that can come back on some z/OS operations. There should also now be a reasonable amount of trace around the area so if the problem recurs, we have a better chance of determining what's going on.