Make bundling for deployment happy

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.

Gemfile

@@ -13,11 +13,7 @@ group :assets do
   gem 'coffee-rails',           "~> 3.2.2"
   gem 'uglifier',               "~> 1.0.0"
   gem 'jquery-ui-rails',        "~> 2.0.0"
-
-  # Many Linux environments do not have a javascript environment which is
-  # required by the asset generators. However, windows and os x have one
-  # provided by the system.
-  gem "therubyracer",           "~> 0.11.3" unless RUBY_PLATFORM.match(/darwin|mswin/)
+  gem "therubyracer",           "~> 0.11.3"
 end
 
 gem "haml",                     "~> 3.1.4"