Add support for forcing in-place encryption
Add support for forcing in-place encryption

Summary: Adds support for indicating AEAD options on write/encrypt, and pipes down from AsyncFizzBase to support forcing in-place encryption.

Reviewed By: mingtaoy

Differential Revision: D28277880

fbshipit-source-id: c8ca593bdbeec3f5fce16ecc4cf61218c21cdc64

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