Remove rails 3.x.x compatibility
Remove rails 3.x.x compatibility from Gemfile
Role: fix dependent "restrict_with_exception" test
Node: do not use dup, copy each attributes line by line

With .dup also awesome_nested_set rft, lgt attributes got duplicated and
therefor making problems when copying nodes.
Fix acts_as_node spec by using Book class
Fix releaf i18n depreciation warning

Fix warning by using find_or_create_by(args) method
Fix "application helper spec" by using new output html
Remove globalize3 fallbacks
BaseController: include joins only when needed
Dummy::Author: fix depreciation warning

by using restrict_with_exception
BaseController: use :restrict_with_exception instead of :restrict
BaseController: fix test by using symbols instead of string