Setting is_measurement for converted state functions and backend arg required to CircuitSampler (Qiskit/qiskit-aqua#1344)
Setting is_measurement for converted state functions and backend arg required to CircuitSampler (Qiskit/qiskit-aqua#1344)

* 1) backend arg required to CircuitSampler
2) setting is_measurement for converted state functions
3) new test case in TestStateOpMeasEvals

* test if is_measurement correctly propagated in CircuitSampler

* test_is_measurement_correctly_propagated simplified

* release note added

Co-authored-by: Steve Wood <df319c8b10182f101be29ecf0d4d148dec6c4bfc@users.noreply.github.com>
Co-authored-by: Julien Gacon <2578673985e8ae3d22330d3daafe06433268eaa0@gmail.com>
QISKit/qiskit-sdk-py,QISKit/qiskit-sdk-py,QISKit/qiskit-sdk-py