Add the detailed info for parameter 'verbose'

[murunlin]

Why are these changes needed?

Add the detailed explanation for parameter 'verbose', which can control the logger level such as ERROR, WARNING messages.

Related issue number

Related to #1428

Checks

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[thinkall]

Thanks for the PR, @murunlin. Could you add the logging level when verbose = 4, 5 and more? And make the description more concise. Thanks.

[thinkall]

Why only (shows ERROR + CRITICAL) and (all messages)? I suggest remove both of them.

As I've tested, verbose 5 will not show all messages, but verbose > 5 will do. Please add info of verbose > 5.

Thanks.