Fix Off Canvas Android Bug

A section tag closed with a div tag breaking the page markup which
caused a bug that surfaced on Android where the off canvas menu was
unusable.
Remove menu resizing JS

This comes for free with off canvas wrap so there shouldn't be any need
for this JS to match the off canvas menu height.
Merge pull request #467 from opscode/fix-off-canvas-android-bug

Fix off canvas android bug and remove unused JS