Python data

[austinschneider]

This PR aims to improve how we are packaging our data.

The main goals are:

• Have the package reference data from its resources directory
• Store generated data from DarkNews in the resources directory
• Version the cross sections, detector models, etc.
• Create a system for managing versions of these models in the context of the LIController and any other methods that perform some sort of automatic/default setup procedure

[austinschneider]

Something is causing the artifact upload stage of the build_wheel jobs to fail, so I don't think the failures are related to anything in the code. I'm assuming the issue was some transient problem with github, so just going to restart the failed jobs until they finish. Otherwise I think this PR is good to go!

[nickkamp1]

Most recent commit ensures that cross section tables are being saved correctly for the DarkNews examples. Fixes bugs not related to this PR. Changes directly related to this PR all look good, approving