Fix floppyforms checkbox attributes template
Fix floppyforms checkbox attributes template

Fixes #593

azavea/nyc-trees,kdeloach/nyc-trees,azavea/nyc-trees,RickMohr/nyc-trees,azavea/nyc-trees,azavea/nyc-trees,azavea/nyc-trees,RickMohr/nyc-trees,maurizi/nyc-trees,RickMohr/nyc-trees,kdeloach/nyc-trees,kdeloach/nyc-trees,RickMohr/nyc-trees,maurizi/nyc-trees,kdeloach/nyc-trees,maurizi/nyc-trees,kdeloach/nyc-trees,maurizi/nyc-trees