load test gems in travis environment too

Gemfile

@@ -99,6 +99,9 @@ gem 'rake', '>= 10.0.0'
 
 group :development, :test do
   gem 'sqlite3'                      # database engine
+end
+
+group :development, :test, :travis do
   gem 'haml-rails'                   # HTML templating language
   gem 'rspec-rails', '~> 2.12.1'     # unit testing framework
   gem 'webrat'                       # provides HTML matchers for view tests