Building OTCryptoPP for review. Do not merge.

Full OTCrypto implementation in CryptoPP.  Same API.

I still need to do OTAsymmetricKey for CryptoPP.

This is half-way work towards using Bitcoin compatible crypto.

Please review:

https://github.com/da2ce7/opentxs/blob/cryptopp/include/opentxs/core/crypto/OTCryptoPP.hpp
https://github.com/da2ce7/opentxs/blob/cryptopp/src/core/crypto/OTCryptoPP.cpp

Cam.
this is not a cryptographic function, maybe we should move it to (OT)Encoding together with the base64 and compression functions.