HACKING.CRYPTO: keep up to date with new crypto definitions from code. (#466)
HACKING.CRYPTO: keep up to date with new crypto definitions from code. (#466)

File: HACKING.CRYPTO

Notes:
This commit updates the HACKING.CRYPTO documentation file in an attempt to make it in sync with current code.
New documented features are:

SHA384
SHA512
ECDSA
ED25519

Credit:
monnerat 
libssh2/libssh2,libssh2/libssh2,libssh2/libssh2,libssh2/libssh2