Move “Exporting and Importing” out of “Configuration”

[chasenlehara]

This creates a separate page for the “Exporting and Importing” exercise that was part of the “Configuration” page. They seemed to have nothing to do with each other, so I think this makes more sense.

Note how the tests are done for the exercise. We instruct learners to add use this for the test script in their package.json:

node --require ts-node/register --test src/**/**.test.**

This will look for any .test. file and run it with Node’s test runner. We do not need Mocha or any other dependency.