Build nokogiri with system libraries on Travis
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Merge pull request #525 from opscode/ghfm

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Merge pull request #529 from opscode/nokogiri-travis

Build nokogiri with system libraries on Travis
Fixes #537 - Upgrade Rails wrt CVE-2014-3482

It was determined that supermarket is *not vulnerable* to this
vulnerability. However, we should upgrade to the latest version of
Rails, for posterity's sake.

CHEF posted about the vulnerability on our blog:

* http://www.getchef.com/blog/2014/07/02/chef-rails-cve-2014-3482/
Merge pull request #538 from opscode/jtimberman/CVE-2014-3482

Fixes #537 - Upgrade Rails wrt CVE-2014-3482
allow admins to combine and delete CCLAs
adding a search scope to CclaSignature
refactor the combine! method
Style organization management view

Write some copy and style organization management view.
ensure no duplicate contributors
strip admin privileges of incoming contributors