fix bug in __setstate__

the state of the object which has been serialized must be used to set
atribute during the deserialisation
add mongokit model of job routing
BIG modification in engine architecture

 due to problems in serialization/deserialization with pickle of jobs
in jobstable (multiprocessing and manager)
    and that the jobs are already serialized in DB
    we decide to serialize jobs only in DB

So the special methods __getstate__ and __setstate__ have been  removed
Merge branch 'develop' of https://github.com/mobyle2/mobyle2.lib into develop