use :order_column option instead of :order for acts_as_nested_set

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012680
back out r12680

<pre>
  1) Failure:
test_children(ProjectTest) [test/unit/project_test.rb:374]:
<[5, 3, 4]> expected but was
<[3, 4, 5]>.
</pre>

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012681
move awesome_nested_set leaf? modification to config/initializers/10-patches.rb

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012682