Clean up module requires

index.js

@@ -1,7 +1,6 @@
-const KeenTracking        = require('keen-tracking');
-const nunjucks            = require('nunjucks');
 const express             = require('express');
 const keenMiddleware      = require('./lib/keen-middleware');
+const nunjucks            = require('nunjucks');
 const nunjucksFilters     = require('./lib/nunjucks-filters');
 const nunjucksMiddleware  = require('./lib/nunjucks-middleware');
 const compression         = require('compression');