Fix mobile navigation

This commit adds a javascript function that collapses the mobile
navigation menu when clicked so that you can actually read what's
below it. It also adds jump anchors that offset the height of the
top bar so that you can read the heading that you navigate to.
add clear property to compensate for bootstrap grid
Merge branch 'fix_mobile_nav' of https://github.com/thenickcox/detroit-water-project into thenickcox-fix_mobile_nav
Merge branch 'thenickcox-fix_mobile_nav'. Awesome fixes.