bugdown: Re-enable support for italics in bugdown.

Fixes: #1103.

static/third/marked/lib/marked.js

@@ -742,7 +742,7 @@ InlineLexer.prototype.output = function(src) {
     // em
     if (cap = this.rules.em.exec(src)) {
       src = src.substring(cap[0].length);
-      out += this.renderer.em(this.output(cap[2] || cap[1]));
+      out += this.renderer.em(cap[1] + cap[2]);
       continue;
     }