Added mac logs, improved mac editing/viewing

app/models/mac.rb

@@ -1,4 +1,6 @@
 class Mac < ActiveRecord::Base
   belongs_to :user
   attr_accessible :active, :ip, :mac, :refreshed, :since, :hidden, :note, :user_id
+
+  validates_uniqueness_of :mac, :case_sensitive => false
 end

app/models/mac_log.rb

@@ -1,3 +1,5 @@
 class MacLog < ActiveRecord::Base
   attr_accessible :action, :ip, :mac
+
+  scope :desc, order("mac_logs.created_at DESC")
 end