Fix of distributed abc smc tests + add of a test.
Preparation for the new feature: add a stop criteria in the simulation.
All tests passed.

The solution is to use FunctionWrappers.jl which provides a high
interface for C function pointers.

All tests passed.

models. It's a better semantic and improve performance as well as
readability of the code. All the tests passes (except the remark in the
last commit).