Add a couple of interface definitions

[bartv2]

see #4863

@DeepDiver1975 @karlitschek @icewind1991 @tanghus @bantu

[DeepDiver1975]

hmmm - if there is a getSystemValue() why not a setSystemValue()?

[bartv2]

Do we want apps to write into config.php? is not really the place to store app values.

[DeepDiver1975]

hmm - where did my comments go?

Well accessing config.php has some sec issues as well like getting access to the password salt, database credentials ...

[ghost]

Test passed.
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[DeepDiver1975]

no return?
no exceptions?

[DeepDiver1975]

return OCP please

[ghost]

Test passed.
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[ghost]

Test passed.
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[ghost]

Test passed.
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[ghost]

Test passed.
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[tanghus]

@DeepDiver1975 Aren't the issues addressed now? Otherwise I think you should make separate PRs for the different cases @bartv2. We need to get this puppy merged :)

[DeepDiver1975]

❓ 😉

[DeepDiver1975]

👍 here we go