Substrate FRAME Storage remove_all API should have a key limit

[hoanglamhuynh]

paritytech/substrate#9002

> Similar to the storage_kill api in child tries, the remove_all api on any maps should also have an optional key limit to enforce weight restrictions.
>
> #8166
>
> When calling remove_all, a user should also be able to include Option<u32>, which describes the maximum number of keys that can be removed at once.
>
> At the end of the operation, you can return AllRemoved(u32) or SomeReamining(u32) with the number of items that were actually removed at the end of the operation.
>
> Should reuse and rename KillChildStorageResult:
>
> https://github.com/paritytech/substrate/blob/master/primitives/io/src/lib.rs#L89

Author: Henry Lam

Link: https://stackoverflow.com/questions/67817077/substrate-frame-storage-remove-all-api-should-have-a-key-limit

[hoanglamhuynh]

This is an exact copy of the text at paritytech/substrate#9002. Why paste this as a question? Can you add more context?

Author: SirDarius