highlight-current-menu

Add this to a general include or functions file somewhere
```
// Get current page name and use that to highlight current page in menu
$current_page = basename($_SERVER['PHP_SELF'], ".php");
```
Then add this to your links:
```
<li class="<?php echo $current_page == 'about' ? 'active' : ''; ?>"><a class="menu-about" href="about">about</a></li>
```