fix firefox active tab highlight bug

Issue

Removed margin-left: -10px and margin-right: -10px from navbar component, which was what caused the bug
Also shortened "Building List" to just "Buildings", partly because the "Building List" text would render on 2 lines without negative margins (on mobile device resolutions, like 600px wide screen), and partly because it's not like we show "Campaign List" instead of "Campaigns
Also replaced "Building List" with "Buildings" in the FAQ ("getting started") tab
Actual component names or code comments referencing "building list" were not changed