Increased test coverage

refs https://github.com/TryGhost/Toolbox/issues/430

- The bonus of using the module exports file is that it also gets included in the test coverage statistics ^_^

ghost/members-csv/test/parse.test.js

@@ -1,6 +1,6 @@
 const should = require('should');
 const path = require('path');
-const parse = require('../lib/parse');
+const {parse} = require('../index');
 const csvPath = path.join(__dirname, '/fixtures/');
 
 const readCSV = ({filePath, mapping, defaultLabels}) => parse(filePath, mapping, defaultLabels);

ghost/members-csv/test/unparse.test.js

@@ -1,5 +1,5 @@
 const should = require('should');
-const unparse = require('../lib/unparse');
+const {unparse} = require('../index');
 
 describe('unparse', function () {
     it('serializes json to CSV and adds standard members fields', async function () {