added heroku and git path for gravtastic to gemfile

Gemfile

@@ -6,11 +6,12 @@ gem 'sqlite3'
 gem 'forum_monster', '~> 1.0.3'
 gem 'devise'
 gem 'cancan'
-gem 'gravtastic'
+gem 'gravtastic', :git => 'https://github.com/chrislloyd/gravtastic.git'
 gem 'bb-ruby'
 
 group :development do
   gem 'hirb'
+  gem 'heroku'
 end
 
 group :production do