* Add the social buttons gem to the Gemfile
* Initializer and translations for the social buttons
* Add the social buttons assets to the sprockets require
* Add the social buttons in the show debate view
* Spec to lock down the amount of social share buttons to three
* Store the last used locale in the session
* Allow home page to be identified in helpers even when containing
parameters
* Create initializer to explicitly set the available locales, the
default and the load_path
