o Code simplification and refactoring:
    - Remove specialized code for non-inplace AES_CTR.  99% of our AES
      is inplace, so there's no need to have a separate implementation
      for the non-inplace code. Closes ticket 18258. Patch from
      Malek.

  o New requirements:
    - Tor no longer supports versions of OpenSSL with a broken
      implementation of counter mode.  (This bug was present in OpenSSL
      1.0.0, and was fixed in OpenSSL 1.0.0a.) Tor still detects, but
      no longer runs with, these versions.