toggle-button
player: fix pause and add song info
add SongView
fix comments bugs
fix sidebar toggling
default view: SongView
Merge remote-tracking branch 'origin/sidebar-toggling' into development

Conflicts:
	frontend/javascripts/main/MainController.js
	frontend/javascripts/sidebar/SidebarController.js
	frontend/javascripts/sidebar/SidebarNavView.js
	frontend/views/index.jade