Move crypto related functions into crypto_toolbox

Also clean up the code:
* remove spurious logging, or replace with DVLOG
* use std::copy and std::reverse_copy instead of ARRAY_TO_STREAM and
  REVERSE_ARRAY_TO_STREAM

Test: CryptoToolboxTest already cover all those functions
Change-Id: I3221d0966d2dd6ca229adf441ceb75dd37a54d7c
Merged-In: I3221d0966d2dd6ca229adf441ceb75dd37a54d7c