Remove crypto's pimpl idiom
Created by: anonimal
We don't need it, I never wanted it, it's annoying to deal with and it's unneeded overhead. Crypto++ is a fine library of which I've worked side-by-side with and I don't foresee it leaving anytime soon. We also don't change our crypto enough to warrant a pimpl design so, simply treating our implementation file(s) as implementation files should suffice - without the need for pimpl.
Removing pimpl won't prevent us from changing libraries. If we end up changing any interfaces in the process of resolving this issue, the changes will be for the better.
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