fix compare_json spec helper in preparation for rails 3

Change-Id: Ibc73cddcd87012ef3776c2c5a99b305fb3c2878b
Reviewed-on: https://gerrit.instructure.com/30869
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Brian Palmer <brianp@instructure.com>
Product-Review: James Williams  <jamesw@instructure.com>
QA-Review: James Williams  <jamesw@instructure.com>

spec/spec_helper.rb

@@ -1267,7 +1267,11 @@ end
         compare_json(a, e)
       end
     else
-      actual.to_json.should == expected.to_json
+      if actual.is_a?(Fixnum) || actual.is_a?(Float)
+        actual.should == expected
+      else
+        actual.to_json.should == expected.to_json
+      end
     end
   end