Expand size and # of horizontal content items in grid view as page size expands instead of just expanding size of sidebar ads

[AdamBLevine]

Currently when grow your window horizontally the border surrounding the content items stretches, the sidebar grows and the ads in the sidebar get larger than their resolution can comfortably display. It would be better to expand the number and potentially increase the size (up to 400x400 which is the native size of the images we ask to be uploaded) of the content items rather than growing the ads.