fixed the readme
fixed the link to repositories in the cabal files
Merge movement of raaz to the raaz-crypto organisation

The raaz repository is now under the raaz-crypto organisation.  These
patches change the links in the cabal files and readme to reflect this
change.
Added functions to convert hexadecimal bytestring to binary bytestring.
added --enable-tests also to all cabal install commands.
Added wrappers for little endian and big endian Words in raaz-core
Added endian-wrappers in raaz-hash
Added endian-wrappers in raaz-modular
Added endian-wrappers in raaz-random
Added endian-wrappers in raaz-cipher
Merge LE and BE types for all words fixes #169.
some refactoring of endian store instances.
recommended blocks is at least 1 whatever be the cache size.
added an os based config selection.
failed cache guess now returns Maybe Int.
Merge avoid recommended from being zero due to small l1cache

- now failed cache size guesses returns Nothing instead of 0
- failed cache guesses are handled by a default value of 32K
- recommended blocks are at least 1.
Merge conversion from hex to binary
Added functions to do signing and verification
Added RSA Signing tests
Fixed performance issue with haskell AES