Add kotlin extensions for Sort.

[nillpoe]

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Closes #3445

[mp911de]

Thanks for your contribution. I think your pull request should not be required once we've merged #3409. Can you check out the code at #3409 to verify typed property paths will achieve what you're looking for?

[nillpoe]

Hi, thanks for the reply. I missed that one because the search for "sort" didn't yield it.
Yes, I think that is another form of Kotlin typed-property support.

But this change will allow you to choose between ascending and descending more easily in most use case.
So I don't really think #3409 closes this PR.

[mp911de]

Introducing an universal extension for ordering can cause confusion in other contexts, additionally, there is much more detail associated with sorting (such as sorting by multiple properties, nulls precedence), therefore we would not want to add this specific extension.