call Project#set_or_update_position_under in Project.rebuild_tree! (#12431)

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012683
back out r12679 awesome_nested_set 2.1.5 modification

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012684
graft r5285 to awesome_nested_set 2.1.5 (#7920)

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012685
remove unneeded Project#acts_as_nested_set :order => 'name' option

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012686
import awesome_nested_set 2.1.6

https://github.com/collectiveidea/awesome_nested_set/commit/64cc8bc8cf93e8859a21bcf25c36675080e42ce6

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012687
add lib/plugins/awesome_nested_set/init.rb

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012688
graft r5285 to awesome_nested_set 2.1.6 (#7920)

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012689