Fix ubuntu deployment

When deploying to heroku or running on travis, I was seeing:

```
    You are trying to install in deployment mode after changing
           your Gemfile. Run `bundle install` elsewhere and add the
           updated Gemfile.lock to version control.
           You have added to the Gemfile:
           * therubyracer (~> 0.11.3)
```

I assume because of the conditional we had for platform. Sooo let's take that out.


This also includes a commit to fix a bunch of duplicated lines in the Gemfile.lock that I didn't see in the commit of wilkie's i just merged because github assumes you don't want to see the Gemfile.lock diff :P