Wiki page protection (#851, patch #1146 by Mateo Murphy with slight changes).

New permission added: protect wiki pages. Once a page is protected, it can be edited/renamed/deleted only by users who have this permission.

git-svn-id: http://redmine.rubyforge.org/svn/trunk@1415 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/wiki_page.rb

@@ -105,6 +105,11 @@ class WikiPage < ActiveRecord::Base
   def text
     content.text if content
   end
+  
+  # Returns true if usr is allowed to edit the page, otherwise false
+  def editable_by?(usr)
+    !protected? || usr.allowed_to?(:protect_wiki_pages, wiki.project)
+  end
 end
 
 class WikiDiff