Fix icons/logos

Author: lefticus

_includes/common.html

@@ -1,4 +1,4 @@
-<link rel="shortcut icon" href="/favicon.ico">
+<link rel="icon" href="/favicon.png">
 
 <!-- Latest compiled and minified CSS -->
 <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css">

favicon.ico

@@ -21,7 +21,7 @@
     <div class="row">
       <div class="col-md-4">
         <h1>ChaiScript</h1>
-        <p><img src="/favicon.ico" align="left"/> an easy to use embedded scripting language for C++.</p>
+        <p><img src="/logo.png" align="left"/> an easy to use embedded scripting language for C++.</p>
         <br/>
         <a class="btn btn-default btn-lg " href="https://github.com/ChaiScript/ChaiScript/releases">Download</a>
       </div>