pep8 fixes, code cleanup, docstring updates
pep8 fixes, code cleanup, docstring updates

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