Fullscreen/bh — pull request #50 by claudiob (2014-11-07 17:59:21+00:00)
Title: Reduce public API methods from PanelRowHelper

Before this PR, including `bh` in an app would include more methods
than necessary for panel rows: methods like `capture_panel_row` that
should only be accessed privately.

This PR extracts those private methods into a new Button class
that includes all the business logic to render elements and edit
attributes (e.g., attach classes), leaving the helper cleaner.