Trim markup output by ajax

In boxes_footer we need to make sure we trim the rendered output.

Somewhere along the way, the blocks, when rendered, began sometimes having a newline at the end of the string of html. When this is delivered to be inserted, it causes ajax.js (the Drupal ajax framework) to wrap it in a

. This causes context ui to be unable to find block in regions as it demands that they be top level elements.

I think the easy fix for right now is to simply trim the output to prevent this issue.

Patch incoming.