Updated Logo for Silicon Valley Devopsdays 2014 based on the TShirt design

I also finally got webby to work to build the site for myself. Even though webby is a dead project I made a pull request to https://github.com/TwP/webby. I got webby to work with Ruby 2.1.2 enough so I could see if the logo looked right :-)

It also required changing `site/tasks/tags.rake` in this project. I'm not including that change in this pull request though. All it was is:
```
-require 'lib/tags_helper.rb'
+require File.expand_path 'lib/tags_helper.rb'
```