Re-work the main layout to be based on my 2-column map viewer example template (http://jumpinjackie.github.io/bootstrap-viewer-template/2-column/index.html)

The benefit of this layout is that we don't have a schizophrenic UI for phablet/mini-tablet displays. As long as the hamburger icon is visible in the navbar, the rest of the layout will act as though it were a phone-based display and the sidebar will fill the entire screen.
Fix up sidebar toggling behaviour
Move the sidebar to the left. The reason for this is a legal one. In order to comply with the Google Maps TOS, the attribution must be shown at all times when the Google Maps layers are visible. It just so happens with this revised layout that the sidebar on the right obscures this attribution. Rather than trying to battle the Google Maps API to re-position this attribution somewhere else, it is more practical and easier to just have the sidebar on the left.
Use container-fluid for navbar body. Although chrome DevTools is telling us the display is messed up on mobile, physically resizing it to such actual dimensions shows something different, leading me to suspect that DevTools is lying to me.