Supporting more kramdown options.

lib/jekyll/converters/markdown/kramdown_parser.rb

@@ -26,7 +26,7 @@ module Jekyll
             # not using coderay
             base_kramdown_configs
           end
-          Kramdown::Document.new(content, kramdown_configs).to_html
+          Kramdown::Document.new(content, @config["kramdown"].symbolize_keys).to_html
         end
 
         def base_kramdown_configs

lib/jekyll/core_ext.rb

@@ -41,6 +41,17 @@ class Hash
     end
     array || []
   end
+
+  def symbolize_keys!
+    keys.each do |key|
+      self[(key.to_sym rescue key) || key] = delete(key)
+    end
+    self
+  end
+
+  def symbolize_keys
+    dup.symbolize_keys!
+  end
 end
 
 # Thanks, ActiveSupport!