Added an active field track if an Enumeration is active on the frontend view.

* Changed TimelogHelper#activity_collection_for_select_options to only use
  active TimeEntryActivities.
* Changed TimelogHelper#activity_collection_for_select_options to return a blank
  option if the time_entry's current activity is inactive.

  #4077

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@2946 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/enumeration.rb

@@ -53,9 +53,17 @@ class Enumeration < ActiveRecord::Base
       find(:first, :conditions => { :is_default => true })
     end
   end
+  # End backwards compatiblity named_scopes
 
   named_scope :all, :order => 'position'
 
+  named_scope :active, lambda {
+    {
+      :conditions => {:active => true},
+      :order => 'position'
+    }
+  }
+
   def self.default
     # Creates a fake default scope so Enumeration.default will check
     # it's type.  STI subclasses will automatically add their own