added vREST logo

I have added vREST logo to the index page. Please review and merge it. Attached is the image how it looks like.

Thanks and regards
Pankaj

![screen shot - - at](https://cloud.githubusercontent.com/assets/46752/4697933/f65c4d3a-582d-11e4-8202-c36d40fa2ce4.png)