merge
merge
simplify implementation of tensor
add check that all superreps for tensor of super operators are equal.
remove empty line
fixed typos
pep8 fixes
import cleanup
clear isherm flag if False, because we cannot be sure that isherm is False after tensor multiplying nonhermitian opeators (the result could be hermitian)
Merge pull request #100 from jrjohansson/refactor-tensor

Refactor tensor