added numpy global import to Qobj (needed by qobj_list_evaluate, which evaluates string expressions that need access to basic numpy functions)
added numpy global import to Qobj (needed by qobj_list_evaluate, which evaluates string expressions that need access to basic numpy functions)

zasdfgbnm/qutip,zasdfgbnm/qutip,qutip/qutip,qutip/qutip,anubhavvardhan/qutip,anubhavvardhan/qutip,cgranade/qutip,cgranade/qutip