merge fix-social-merge

Gemfile

app/assets/javascripts/application.js

app/assets/stylesheets/application.scss

app/controllers/callbacks_controller.rb

app/helpers/learning_objects_helper.rb

app/models/user.rb

app/views/devise/sessions/new.html.erb

app/views/devise/shared/_links.html.erb

app/views/layouts/application.html.erb

app/views/learning_objects/_share_modal.html.erb

app/views/learning_objects/show.html.erb

app/views/users/_header.html.erb

config/initializers/devise.rb

config/initializers/social_share_button.rb

config/locales/pt-BR.yml

config/routes.rb