move bundle config to JSON format

[askpatrickw]

Fixes #125

1. This moves the configuration of bundles to a JSON file: bundle_config.json which is added to the setup.py data_files. It is assumed to be in sys.prefix.
2. Fixes a test which was verifying the use of the old method, by using a test_bundle_config.json
3. Changes test_bundle_name to use the test_bundle_config.json value
4. Running the tests didn't work with the first way I was including the config file. I change circup to a package layout, installed it as as package and included the config as package data to fix this and the tests.

[askpatrickw]

Looking at the failures... they initially passed on my end. But I can reproduce the failure now.

[askpatrickw]

Comment 4 on the description describes how I fixed the tests. Not sure its the best way. But worked.

[askpatrickw]

We should rev the major version number if we merge this. It might be a breaking change for anyone using the circup.py file name directly.

[jepler]

Makes sense but didn't test.

[jepler]

As an improvement, consider using https://pypi.org/project/appdirs/ so that you can look for the config json file first in the user's configuration directory and then to the default list shipped in the package.

[ladyada]

fyi @tannewt @jwcooper

[askpatrickw]

@jepler Good idea... Do you see that overriding the default or supplementing the default?

[Neradoc]

My idea for supporting 3rd party bundles was to have new commands (bundle-add, bundle-remove, bundle-info) that manage a separate list, while the default bundles would always remain. But the ability to override the default list, to maybe disable built-in ones, or change the order (to have a 3rd party neopixel implementation override the adafruit one for example) seems a possibly useful idea. Maybe adding also a bundle-reset command to reset the list to the default one.

[jepler]

Probably supplementing the regular list.. (figuring it out silent block this PR from being merged)

[askpatrickw]

We could merge this as-is and then work out the design for these other ideas in a new issue.
They're much larger than the original ask.

[askpatrickw]

I opened an issue on the 3rd Party Bundle Support - 127. So we can move this PR along.