bench against commonmark instead of showdown, which is super slow

package.json

@@ -23,14 +23,14 @@
     "html"
   ],
   "devDependencies": {
-    "markdown": "*",
-    "showdown": "*",
-    "markdown-it": "*",
     "front-matter": "^2.3.0",
     "glob-to-regexp": "0.3.0",
     "gulp": "^3.8.11",
+    "gulp-concat": "^2.5.2",
     "gulp-uglify": "^1.1.0",
-    "gulp-concat": "^2.5.2"
+    "markdown": "*",
+    "markdown-it": "*",
+    "commonmark": "0.x"
   },
   "scripts": {
     "test": "node test",

test/index.js

@@ -262,22 +262,16 @@ function runBench(options) {
 
   // showdown
   try {
-    bench('showdown (reuse converter)', files, (function() {
-      var Showdown = require('showdown');
-      var convert = new Showdown.Converter();
+    bench('commonmark', files, (function() {
+      var commonmark = require('commonmark')
+        , parser = new commonmark.Parser()
+        , writer = new commonmark.HtmlRenderer();
       return function(text) {
-        return convert.makeHtml(text);
-      };
-    })());
-    bench('showdown (new converter)', files, (function() {
-      var Showdown = require('showdown');
-      return function(text) {
-        var convert = new Showdown.Converter();
-        return convert.makeHtml(text);
+        return writer.render(parser.parse(text));
       };
     })());
   } catch (e) {
-    console.log('Could not bench showdown. (Error: %s)', e.message);
+    console.log('Could not bench commonmark. (Error: %s)', e.message);
   }
 
   // markdown-it