Merge branch 'fix_keyboard_a11y_step_bullets' of https://github.com/nelsonwong1012/intro.js into nelsonwong1012-fix_keyboard_a11y_step_bullets

Conflicts:
	intro.js

Author: bozdoz

intro.js

@@ -331,6 +331,9 @@
         }
 
         _exitIntro.call(this, this._targetElement);
+      } else if (target && target.getAttribute('data-stepnumber')) {
+        // user hit enter while focusing on step bullet
+        target.click();
       } else {
         //default behavior for responding to enter
         _nextStep.call(this);