Merge safety now on primitives rather than gadgets fixes #80
renamed newGadget as newGadgetWithMemory
gadget tests fixed
fixed SHA1 gadgets
fixed SHA224 gadgets
fixed Sha512 gadgets
fixed SHA256 gadgets
fixed SHA384 gadgets
fixed gadget benchmarks
Merge name change of newGadget

* Renamed newGadget to newGadgetWith memory
* Exported additional combinators
  - newGadget: This creates a gadget with its memory allocated using newMemory
  - newInitializedGadget: newGadget + initialization
CipherGadget and StreamGadget added.
Added size parameter to initializable
cellModify added in the Memory API
Random Number generator added
Standard functions for writing test cases for ciphers.
Adding raaz-random to Makefile.configure
Merge interfaces for random bytes generators and ciphers
Rename BookKeeper to PoolRef
Memory instance for Buffer
Secure Memory cleaned