Remove unused key :preview from Redmine::AccessKeys::ACCESSKEYS (#34444).

Patch by Go MAEDA.


git-svn-id: http://svn.redmine.org/redmine/trunk@20705 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/access_keys.rb

@@ -22,7 +22,6 @@ module Redmine
     unless const_defined?(:ACCESSKEYS)
       ACCESSKEYS = {
         :edit => 'e',
-        :preview => 'r',
         :quick_search => 'f',
         :search => '4',
         :new_issue => '7',