Bump default version of Ruby and rubygems.
Bump elasticsearch to 0.90.2.
Bump nginx cookbook to fix duplicate attributes.
Update ark cookbook to newer version from opscode.
Bump to passenger 4.0.8. Fix some config deprecations with v4.
Bump some cookbooks to newer versions.
Add role for yum setup.
Bump nodejs to 0.10.13.
Bump mongodb. Bump cookbook to fix conflicting init.d names in RHEL.
Add checksum for elasticsearch tar.gz to prevent redownloads.
Bump nodejs to v0.10.15
Bump redis to 2.6.14.
Update elasticsearch cookbook.
Add Varnish to stack for optional caching layer.
Bump passenger to 4.0.10.
Setup changed for the switch to using nginx as the main router.

See here for details on switch:
https://github.com/NREL/api-umbrella-router/commit/118c3a1467110a4997ac7ab706098c5870786f8e
Merge branch 'master' of http://github.com/NREL/api-umbrella