added autofocus and tabsise

Author: whoisandy

src/editor.js

@@ -90,8 +90,10 @@ Editor.prototype.render = function(el) {
   this.codemirror = CodeMirror.fromTextArea(el, {
     mode: 'markdown',
     theme: 'paper',
+    tabSize: '2',
     indentWithTabs: true,
     lineNumbers: false,
+    autofocus: true,
     extraKeys: keyMaps
   });