use initialize/render flow for markup

lib/gollum/markup.rb

@@ -1,14 +1,30 @@
 module Gollum
   class Markup
-    # Render the content with Gollum wiki syntax on top of the file's own
-    # markup language.
+    # Initialize a new Markup object.
     #
     # name - The String filename of the page.
     # data - The String contents of the page.
     #
+    # Returns a new Gollum::Markup object, ready for rendering.
+    def initialize(name, data)
+      @name = name
+      @data = data
+      @tagmap = {}
+    end
+
+    # Render the content with Gollum wiki syntax on top of the file's own
+    # markup language.
+    #
     # Returns the formatted String content.
-    def self.render(name, data)
-      GitHub::Markup.render(name, data) rescue nil
+    def render
+      base_markup = GitHub::Markup.render(@name, @data) rescue nil
+    end
+
+    # Extract all tags into the tagmap and replace with placeholders.
+    #
+    # Returns nothing.
+    def extract_tags
+
     end
   end
 end

lib/gollum/page.rb

@@ -35,7 +35,7 @@ module Gollum
     #
     # Returns the String data.
     def formatted_data
-      Gollum::Markup.render(@blob.name, @blob.data) rescue nil
+      Gollum::Markup.new(@blob.name, @blob.data).render rescue nil
     end
 
     # Public: The format of the page.