Merge pull request #147 from wanderrful/fix-periphery-rules

docs: Fix final rule being incorrectly excluded

Fixes #75

Prior behavior was that the final element of the `rows` list would be removed for _every_ Rule in the CSV file when the rule did not contain a "Use"+"Explanation" section.  This PR puts a sanity check on that logic so that we only do it we actually need to (i.e. when a "Use"+"Explanation" section is present in the rule).