put back in known checks for Hermicity and type.  Also removed multiplication by a 1D qobj as this operation is never used.
put back in known checks for Hermicity and type.  Also removed multiplication by a 1D qobj as this operation is never used.

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