Refactor view code a little bit

Conflicts:
	app/helpers/application_helper.rb
	app/helpers/topics_helper.rb
	app/views/layouts/application.html.slim
	app/views/replies/_reply.html.slim
	app/views/topics/_social_share.html.slim
	app/views/topics/_tools.html.slim
	app/views/topics/_topic.html.slim
	app/views/topics/show.html.slim