added examples and removed hadamard gate as it conflicted with the scipy definition and is the same as the snot gate that is already included
added examples and removed hadamard gate as it conflicted with the scipy definition and is the same as the snot gate that is already included

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