Refactoring and new bindings.

+ Refactored Code to be cleaner.
+ Added new bindings for Encrypt constants.
+ Added dummy prototypes for Asymmetric KeyPair/Encrypt/Decrypt operations.
+ Documented Encrypt bindings with the C function prototypes.
Added initial binding support for libSodium Random.
Added base bindings for other crypto primitives.

+ Signing has been included
+ Public and Secret Key Encryption has been included.