Allow for suppressing warnings in NoiseModel.from_backend()

[nonhermitian]

Summary

The larger devices always have one or more bad gates that trigger warnings. This allows for suppressing these.

Details and comments

[atilag]

One of the features we have with Python logging system, is that users can filter any Warning they want by doing:

import logging
class WarningFilter(logging.Filter):
    def filter(self, record):
        return not record.getMessage().startswith('Device model')

logger = logging.getLogger("models")
logger.addFilter(WarningFilter())

This will filter all messages starting with "Device model" string, in the models.py file.
If you don't really mind about the warnings at all, you can just disable them:

logging.disable(logging.WARNING)

[nonhermitian]

Ok. But it is unclear what that has to do with the current PR that just extends similar functionality that is already in the code base, e.g.:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 398 in 1cff17f

elif warnings:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 455 in 1cff17f

logger.warning(

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 465 in 1cff17f

if warnings:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 528 in 1cff17f

if warnings:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 540 in 1cff17f

if warnings:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 609 in 1cff17f

if warnings:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 654 in 1cff17f

if warnings:

qiskit-aer/qiskit/providers/aer/noise/noise_model.py

Line 664 in 1cff17f

logger.warning(

[nonhermitian]

Ok, now I see, the above does do what I need since I am an interested in using this in a module.

Edited as it does not actually work.

[atilag]

So you pointed out to something that I call technical debt. We shall not couple logging behavior with function parameters, it does only increases coupling between these components and makes things harder to test.
This is the reason why loggers are singletons (unique global instances).

Ok, let's merge this if you find it useful.