Crypto: encrypt/decrypt, move cryptopp to implementation, tests.

Note: ECDH and ECDHE key exchange are still under development. I would like these schemes to be reviewed however encrypt/decrypt is primary focus; ECDH-related classes and tests will be removed along with ECKeyPair prior to merge.
CS.txt: 4a: as thesetext is an output parameter, it's actually.... o_text.
Also, rename to _cipher so as to be clear.