Merge pull request travis-ci#547 from travis-ci/cd-after-number

Improve query for listing builds `after-number` (i.e. builds `older_than`)

Author: carlad

lib/travis/model/build.rb

@@ -130,7 +130,7 @@ def last_state_on(options)
     end
 
     def older_than(build = nil)
-      scope = descending.paged({}) # TODO in which case we'd call older_than without an argument?
+      scope = order('number::integer DESC').paged({}) # TODO in which case we'd call older_than without an argument?
       scope = scope.where('number::integer < ?', (build.is_a?(Build) ? build.number : build).to_i) if build
       scope
     end