fix wiki page errors

app/controllers/wiki_pages_controller.rb

@@ -70,7 +70,7 @@ class WikiPagesController < ApplicationController
     if @wiki_page
       redirect_to wiki_page_path(@wiki_page)
     else
-      @wiki_page = WikiPage.new(params[:wiki_page])
+      @wiki_page = WikiPage.new(:title => params[:title])
       respond_with(@wiki_page)
     end
   end

app/logical/post_sets/wiki_page.rb

@@ -2,7 +2,7 @@ module PostSets
   class SearchError < Exception
   end
 
-  class WikiPage < Post
+  class WikiPage < PostSets::Post
     def presenter
       @presenter ||= ::PostSetPresenters::WikiPage.new(self)
     end

app/presenters/post_set_presenters/wiki_page.rb

@@ -1,5 +1,5 @@
 module PostSetPresenters
-  class WikiPage < Post
+  class WikiPage < PostSetPresenters::Post
     def posts
       @post_set.posts
     rescue ActiveRecord::StatementInvalid, PGError