drop wigner_ from function name for logarithmic_negativity
drop wigner_ from function name for logarithmic_negativity

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