Support multibyte description

To out put file as "#{md5}.html"

Author: mataki

lib/rspec_api_documentation/html_writer.rb

@@ -73,7 +73,7 @@ def dirname
 
     def filename
       basename = description.downcase.gsub(/\s+/, '_').gsub(/[^a-z_]/, '')
-      basename = URI.encode(description) if basename.blank?
+      basename = Digest::MD5.new.update(description).to_s if basename.blank?
       "#{basename}.html"
     end
 

spec/html_writer_spec.rb

@@ -49,7 +49,8 @@
     let(:example) { group.example(label) {} }
 
     it "should have downcased filename" do
-      html_example.filename.should == URI.encode(label) + ".html"
+      filename = Digest::MD5.new.update(label).to_s
+      html_example.filename.should == filename + ".html"
     end
   end
 end