Updated Omnibus 2.0 with minimal metadata fixes
Vendor `chef-gem` and `libffi` software definitions

Ohai 7.2.0 was just released and has a dependency on the `ffi` gem which
ships with a native extension which requires `libffi`. The fix is to add
a proper dependency on `libffi` in the `chef-gem` software definition.

We can’t simply update to the latest ominibus-software as this project 
is still on Omnibus 2.0.x. The alternate is to vendor the affected 
software definitions tweaked for the Omnibus 2.0 DSL.
Merge pull request #80 from opscode/schisamo/chef-requires-libffi

Vendor `chef-gem` and `libffi` software definitions
Fix the paths in the wait-for-rabbit script
Update Changelog with note about fix for wait-for-rabbit script
Merge branch 'mm/fix-rabbit-wait'
Add support for TLS 1.1 / 1.2 to Nginx config
Remove SSLv3 and update ciphers

Using the Mozilla recommended cipher suite from
https://wiki.mozilla.org/Security/Server_Side_TLS#Recommended_Ciphersuit
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