Qiskit support

[anpaz]

Is your feature request related to a problem? Please describe.
It would be nice to have a way to generate qviz's json from a Qiskit QuantumCircuit object.

Describe the solution you'd like
Something on the lines of adding a creating a convert_to_qviz() method that takes a Qiskit's Circuit object and returns a dictionary/ojbect that can be serialized to the json that qviz supports. For example:

import json

from qiskit import QuantumCircuit
from quantum_viz import convert_to_qviz

circuit = QuantumCircuit(2, 2)
circuit.name = "Qiskit Sample - Bell circuit"
circuit.h(0)
circuit.cx(0, 1)
circuit.measure([0,1], [0, 1])

qviz = convert_to_qviz(circuit)
print(json.dumps(qviz))

[jond01]

Hi, I'd like to take this one :)