title: leaflet sidebar v2: adding buttons & icons
body: <p>I was wondering if anyone figured out a way to add more buttons onto the sidebar with custom icons. It seems like it would be very useful to have the ability to add buttons along the sidebar pane. Any help on this would be appreciated! 
  Here is the link to the sidebar: <a href="https://github.com/Turbo87/sidebar-v2" rel="nofollow">https://github.com/Turbo87/sidebar-v2</a></p>