removed quantum program from tomography module

[chriseclectic]

Summary

Removes dependency on QuantumProgram from the tomography module.

Removed depreciated interface wrapper from qiskit 0.3.

Details

The function create_tomography_circuits now takes as input a quantum circuit object instead of a quantum program and a circuit name string:
create_tomography_circuits(qp, name, ...) ---> create_tomography_circuits(circuit, ...)
build_wigner_circuits(qp, name, ...) ---> build_wigner_circuits(circuit, ...)

It returns a list of quantum circuit objects that may be executed, rather than needing to extract the circuits from a quantum program.

Tests have been updated to new format and pass.

The tutorials for state tomography, process tomography, and wigner tomography will need updating.

Example

# Bell state tomography example

from qiskit import execute, QuantumCircuit, QuantumRegister, ClassicalRegister
from qiskit.tools.qcvv import tomography as tomo

qr = QuantumRegister(2)
cr = ClassicalRegister(2)
bell = QuantumCircuit(qr, cr, name='Bell')
bell.h(qr[0])
bell.cx(qr[0], qr[1])

tomo_set = tomo.state_tomography_set([0, 1])
tomo_circs = tomo.create_tomography_circuits(bell, qr, cr, tomo_set)
result = execute(tomo_circs, 'local_qasm_simulator', shots=shots, seed=42).result()
data = tomo.tomography_data(result, circuit.name, tomoset)
rho = tomo.fit_tomography_data(data)

✅ I have added the tests to cover my changes.
✅ I have updated the documentation accordingly.
✅ I have read the CONTRIBUTING document.