Introduce mimetype DB update occ command

[RobinMcCorkell]

This occ command allows mimetypes in the database to be updated from changed mimetypes in config/mimetypemapping.json. By default, it adds any new mimetypes it finds and updates the filecache based on those, but with an option it can scan all existing mimetypes to update mimetypes on files.

For example, you add a new mapping of '.foo' to 'application/foobar', but your existing '.foo' files still have the 'application/octet-stream' mimetype since they were uploaded before. Run ./occ maintenance:mimetype:update-db to update this. Or, if the 'application/foobar' mimetype already existed, ./occ maintenance:mimetype:update-db --repair-filecache (will be a lot slower for big filecaches!).

Please review @rullzer @icewind1991 @MorrisJobke @PVince81 @icewind1991 @DeepDiver1975

cc @carlaschroder for documentation around the new occ command, and rename of the maintenance:mimetypesjs command to maintenance:mimetype:update-js

Fixes #17625

[karlitschek]

good idea 👍

[icewind1991]

👍 code looks good, saw it work

[rullzer]

Looking good!
And works!
👍

But we really should have tests for this as well (I know I did not write them either...)
Also remember to also update the existing docs since the command is changed.

[nickvergessen]

Alphabetic order 🙊

[RobinMcCorkell]

You mean like the rest of the file is? 😆

[RobinMcCorkell]

Well, doing it properly turned out to be a lot more work than expected, but at least some code smell has been removed. Everything is unit tested too

[scrutinizer-notifier]

A new inspection was created.

[icewind1991]

Looks good 👍

[rullzer]

Looks good and everything seems to work. 👍
Thanks for the tests :)

[oparoz]

Awesome! :)

[carlaschroder]

But I like code smell. It smells like victory.

[nickvergessen]

Regression: master unit tests are broken:

#18975