Remove repeated grid style classes
Remove content extensions, cut down on var calcs
Merge pull request #2180 from darkwing/grid-cleanup

Remove repeated grid style classes
Merge pull request #2183 from darkwing/document-content-updates

Remove content extensions, cut down on var calcs
removed window._gaq closure
avoids non-track of events when async library loads
before bottom of page scripts. `_gaq` pushes should
instead proxy through `mdn.analytics.trackEvent`
Merge pull request #2170 from tomfuertes/master

removed window._gaq closure