Summary: Swaps out AphrontPanels for ObjectBoxes. I'd like to start reducing the floating object lists around the site for consistency. Also, these should provide more items above the fold.
Test Plan:
Test on my local homepage. Built a fake welcome.html too, though I think that's deprecated.
{F277020}
{F277021}
Reviewers: btrahan, epriestley
Reviewed By: epriestley
Subscribers: Korvin, epriestley
Differential Revision: https://secure.phabricator.com/D11529
