Added code block normalization routing for import

lib/import/normalize.rb

@@ -0,0 +1,12 @@
+# markdown normalizer to be used by importers
+#
+#
+require 'htmlentities'
+module Import::Normalize
+  def self.normalize_code_blocks(code, lang=nil)
+    coder = HTMLEntities.new
+    code.gsub(/<pre>\s*<code>\n?(.*?)\n?<\/code>\s*<\/pre>/m) {
+        "\n```#{lang}\n#{coder.decode($1)}\n```\n"
+    }
+  end
+end