Added gadget and primitive composition
Added functions to do signing and verification
Added RSA Signing tests
Fixed performance issue with haskell AES
Moved initialize and finalize to Memory from Gadget to new classes.
Added defaultCxt in Hash type class
Sha family of hashes fixed for change in memory interface
Fixed Blake for change in memory
Fixed Hash Tests
Fixed Hash Benchmarks
Ciphers fixed for Memory interface change
Cipher tests fixed for memory interface change
Fixed raaz-random for memory interface change
Fixed raaz-modular for memory interface change