add support for pre tags in dtext

app/logical/d_text.rb

@@ -202,7 +202,7 @@ class DText
 
     Sanitize.clean(
       text,
-      :elements => %w(code center tn h1 h2 h3 h4 h5 h6 a span div blockquote br p ul li ol em strong small big b i font u s),
+      :elements => %w(code center tn h1 h2 h3 h4 h5 h6 a span div blockquote br p ul li ol em strong small big b i font u s pre),
       :attributes => {
         "a" => %w(href title style),
         "span" => %w(class style),

app/logical/post_sets/post.rb

@@ -38,10 +38,6 @@ module PostSets
     end
 
     def posts
-      if tag_array.size > 2 && !CurrentUser.is_privileged?
-        raise SearchError.new("Upgrade your account to search more than two tags at once")
-      end
-
       if tag_array.any? {|x| x =~ /^source:.*\*.*pixiv/} && !CurrentUser.user.is_builder?
         raise SearchError.new("Your search took too long to execute and was canceled")
       end