perf: add parallelization

[gabyx]

Proposed Changes

• Add parallelization over rayon which lets you convert an iterator to a ParallelIterator which
  is parallelized over rayon's thread pool.
  Note: rio's into_iterator is abit stupid written, dont see the intention to store a full Vec<T>

• Add a CLI flag --parallel which will use parallelization

• If the parallelization pays out has yet to be tested. The Mutex on the Writer is not particularly good I guess. -> use slogs async writter which is buffered and is Send + Sync...

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Further Comments

[cmdoret]

The clippy settings and code cleanup are welcome additions, but the parallelization of tripsu index degrades performance on my side (see comments).

[gabyx]

@cmdoret , @supermaxiste : the write call on Writer was wrong, only clippy mentioned this: -> write returns how many bytes have been written, which was ignored lol, I thought is a general error =), not all bytes being written is a possibility. So the correct function here is write_all. 👍

[gabyx]

@gabyx : This PR is draft, and should be revisited once parallelization is needed with longer work on the pseudonomization function