[Feature]: Notify user if python package for extension exists and is recommended

[rly]

What would you like to see added to PyNWB?

1. Include a flag in the NWB catalog entry for an extension that says installing the python package is recommended
2. In PyNWB, when loading an extension namespace, e.g., from an NWB file or from a namespace YAML file, if the catalog entry exists and that flag = true, then print a warning to the user to install the python package.

We would update the API regularly with a list of extensions in the catalog that have the flag = true.

Is your feature request related to a problem?

Some extensions have python packages that add extra functionality like object mappers and validation. The extension creator might want users of data from their extension to interact with the data using their python package. We could do something similar for Matlab.

What solution would you like?

See above.

Do you have any interest in helping implement the feature?

Yes.

Code of Conduct

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