rm parameter class, fix #124

- now replaced by simpler and better code generation solution
- TODO: write the documentation, implemented for cthyb solver
[wrapper] Split the converters code, fix #121 and hello_world

- The wrapper_tools.hpp is split into several converters/xxx.hpp
- to include only on demand.
- This fixes the hello_world from the paper
Fix #145 : Compilation on Ubuntu 14.04 32 bits

- one integer type was wrong
- detection of python : patch is different for 32 bits than the usual path in 64 bits.
Fix #152
[gfs] Fix out of bound error in fit_tail

- n_max must be checked against max size of mesh
  or bad input in python will lead to undefined behaviour,
  random results and valgrind error....

- At this stage, I leave the ENFORCE_CHECK macro in fit_tail.cpp
  for checks.
  TO BE REMOVED when code is reviewed.
Silence some gcc warnings.