Fix styling on surveyed blocks
Fix styling on surveyed blocks

This fix ensures that blocks do not appear as available on the
reservations page after they have been surveyed.

Connects #1247

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