Extract cryptographic system interfaces
Add ElGamalKeyGenerator class
Correct ElGamal key generator implementation
Move common classes to the shared project
Create ElGamalSignature class
Create ElGamalSigner class
Create ElGamalVerifier class
Add throw clauses when ctor parameters are null
Create a Signer interface, use where possible
Move classes and implement an interface
Add a dependency for ElGamal on Sha1 project
Resolve message hash problem
Create ElGamalScheme class