skeleton system configration detector written
added some helper functions
added the system parameters type
added an inform function
added linux specific configurations
exposes infered system parameters to the haskell world
Merge system parameter detection fixes #37.

The way it works is as follows

1. The configure script executes the haskell file configure.hs which
   creates the raaz/system/parameters.h file. This file is also
   installed and can be used by other FFI code.

2. The Raaz/System/Parameters.hsc exposes the constants in
   raaz/system/parameters.h. So haskell world can directly use those
   constants.

Currently Linux is the only supported platform. The configure route
can work on any Unix like platform but no meaningful parameters are
read out. This is work for future.
system parameters configured directly through hooks, fixes #42.

The autoconfHook is gone and we explictly generate the system
parameters in the Setup.lhs file itself. This has the following
advantages:

1. It overcomes the cabal bug and fixes #42.

2. This is more likely to work in non-Unix platforms as well as there
   is no more dependency to a shell.
config:linux handles non-existence of sys files, fixes #42
raaz-primitives: removed dependency on data-default
raaz-primitives: removed dependency on text
Implementation class added to raaz-primitive