fork system call

When the process has forked, we must duplicate the whole capabilities chained list, and the overloads of the permissions chained list. We must also ensure that the new process inherit the LFS master of its parent, that the tags inherited from tags referenced by the LFS master are added to the references (lfs chained list) of the LFS master. If the LFS master forks, the child doesn't inherit the lfs chained list.