Added the ability to destroy wiki pages (content and its history are deleted from the database).

This permission has to be explicitly given (Roles & Permissions -> Wiki pages/Delete).

git-svn-id: http://redmine.rubyforge.org/svn/trunk@540 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/permission.rb

@@ -32,6 +32,7 @@ class Permission < ActiveRecord::Base
     1300 => :label_attachment_plural,
     1400 => :label_repository,
     1500 => :label_time_tracking,
+    1700 => :label_wiki_page_plural,
     2000 => :label_board_plural
   }.freeze