Adding images and more comment on Travis

index.html

@@ -7,6 +7,7 @@ excerpt: "Data parallel C++ mathematical object library."
 permalink: /
 header:
   overlay_color: "#5DADE2"
+  overlay_image: header_bg.jpg
 intro:
   - excerpt: 'Get notified when we add new stuff &nbsp; [<i class="fa fa-github"></i> watch project](https://github.com/paboyle/Grid/subscription){: .btn .btn--info}'
 downloads: