remove unnecessary ruby 1.8 reference from active_record/core [ci skip]

Author: Francesco Rodriguez

activerecord/lib/active_record/core.rb

@@ -10,9 +10,10 @@ module Core
     included do
       ##
       # :singleton-method:
-      # Accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class,
-      # which is then passed on to any new database connections made and which can be retrieved on both
-      # a class and instance level by calling +logger+.
+      #
+      # Accepts a logger conforming to the interface of Log4r which is then
+      # passed on to any new database connections made and which can be
+      # retrieved on both a class and instance level by calling +logger+.
       config_attribute :logger, :global => true
 
       ##