added cylic colormap for the phases in the plotting function for complex matrix
added cylic colormap for the phases in the plotting function for complex matrix

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