add missing documentation of nativeOnMobile property and fix a small typo

Author: gearsdigital

public/index.html

@@ -219,6 +219,12 @@ <h2>Options</h2>
      */
     disableOnMobile: true,
 
+    /*
+     * Type: Boolean
+     * Description: Retain native dropdown behavior on mobile devices
+     */
+     nativeOnMobile: true,
+
     /*
      * Type: Boolean
      * Description: Open select box on hover, instead of click
@@ -254,7 +260,7 @@ <h2>Options</h2>
 
     /*
      * Type: String or Function
-     * Description: Define how each option should be rendered inside its <li> element.
+     * Description: Define how each option should be rendered inside its &lt;li&gt; element.
      *
      *              If it's a string, all keys wrapped in brackets will be replaced by
      *              the respective values in itemData. Available keys are: