Added png favicon icon

Signed-off-by: Jim Martens <github@2martens.de>

_data/author.yml

@@ -2,6 +2,7 @@ name: Jim Martens
 image: /assets/images/author.jpg
 brand: 2martens
 brand_logo: /assets/images/brand.svg
+brand_logo_png: /assets/images/brand.png
 image_desc:
 age: 24
 location: Hamburg, Germany

_includes/head.html

@@ -34,6 +34,7 @@
     <link rel="canonical" href="{{ page.url | replace:'index.html','' | prepend: site.baseurl | prepend: site.url }}">
     <link rel="alternate" type="application/rss+xml" title="{{ site.title }}"
           href="{{ site.baseurl }}{% link feed.xml %}">
+    <link rel="icon" href="{{ site.data.author.brand_logo_png }}" type="image/png">
 
     <script>
         FontAwesomeConfig = { autoAddCss: false }