Don't have a cow, man!

Remove cow => kine from default inflections but leave the test case
in place to prevent regression of the [old Trac ticket 4929][1].

[1]: http://web.archive.org/web/20090314050915/http://dev.rubyonrails.org/ticket/4929

activesupport/lib/active_support/inflections.rb

@@ -57,7 +57,6 @@ module ActiveSupport
     inflect.irregular('child', 'children')
     inflect.irregular('sex', 'sexes')
     inflect.irregular('move', 'moves')
-    inflect.irregular('cow', 'kine')
     inflect.irregular('zombie', 'zombies')
 
     inflect.uncountable(%w(equipment information rice money species series fish sheep jeans police))