False values for custom fields are now correctly exported. Fixes #250.

lib/locomotive/export.rb

@@ -305,7 +305,7 @@ module Locomotive
             content.send(field.safe_alias.to_sym)
           end)
 
-          hash[field._alias] = value unless value.blank?
+          hash[field._alias] = value if value.present? || value == false # False values should be preserved in the export
         end
 
         data << { content.highlighted_field_value => hash }

spec/lib/locomotive/export_spec.rb

@@ -25,7 +25,8 @@ describe Locomotive::Export do
     end
 
     it 'deals with real booleans' do
-      @project_data.first.values.first['active'].should be_true
+      @project_data.first.values.first['active'].should === true
+      @project_data.last.values.first['active'].should  === false
     end
 
     it 'stores the list of highlighted values in a has_many relationship' do