Quick rename of question categories (Legacy)

Hi,
In Moodle 4.0, the question bank has changed quite a lot (see https://docs.moodle.org/dev/Question_bank_improvements_for_Moodle_4.0).
In particular, there is a new type of plugin: qbank_.... This should be documented at https://docs.moodle.org/dev/Question_bank_plugins, but I am afraid that this is not complete yet. (However, there is information in the upgrade.txt files in the code, and the PHPdocs in the code should explain things.)
So, I think it is a case of
Bad news: you will have to re-write all your local plugins as qbank plugins to work with Moodle 4.0+.
Good news: if you do, then they will probably work even better for users and you can probably reuse almost all of your code.
There are a lot of references in question/bank directory in Moodle 4.0 repository. Please do not hesitate to get in touch if you have any questions.
Cheers!

Hi Vadim,
I did not find any problems with your plugin, it works as expected and code is ok, thank you. Think David will be in touch shortly about next steps
I noticed using of an $_POST variable, but this seems explainable in this context, as optional_param* functions are apparently unable to handle an array of arrays. PARAM_RAW for submit buttons were also strange only at the first glance, but later on they're also turned out completely ok

Thanks Vadim for sharing this plugin with the Moodle community. I am going to review the plugin, will get back to you with the results later

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