Gemfile: update Rails 3.2.18

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4013130
remove unneeded trailing ';' from test/functional/repositories_git_controller_test.rb

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4013131
remove unneeded trailing ';' from lib/redmine/export/pdf.rb

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4013132