prevent Apache syntax errors if includes are not set
Initialize node["opsworks"].
Adapt Ruby package names for Amazon Linux.
Update MRI ruby patch levels to lastest availables.
Merge branch 'master-chef-11.4' into mainline-chef-11.4
allow to set HAProxy stats socket level, keep empty default
Handle EPEL repository not available

Make built-in layers/cookbooks resilient against EPEL unavailability.
If packages can be found in EPEL, EPEL will be preferred over the
standard Amazon repo. This can break the built-in layers if EPEL has
availability problems.

* Make yum skip the EPEL repository on errors
* Ignore failure of installation of logcheck for Gangle monitoring
  Apache
* Handle case where some PHP Pear packages cannot be installed
  as they originate in EPEL
Merge branch 'master-chef-11.4' into mainline-chef-11.4
Compression for application/json in nginx
Adjust NGinx and Apache mimetype settings for compression.

Enable compression for same set of mime-types in both Apache and NGinx.
Introduce node[:apache][:deflate_types] attribute.

Move mime-types for which mod_deflate is active into attribute
file. This allows the user to customize these types. In addition this
also aligns NGinx and Apache cookbooks.
Use 'ntp' on all platforms.

Previously OpsWorks would use 'openntp' on Ubuntu/Debian, but 'ntp' on
Red-Hat-ish. Having same package on all platforms should lower support
efforts for OpsWorks and give better overall customer experience.
Add metadata.rb for unicorn.
Update default versions:

Bundler --> 1.5.1
Passenger --> 4.0.33
Unicorn --> 4.7.0

Only the unicorn change will actually have much effect as the rest is
usually set via the OpsWorks backend in the Chef JSON.
NGinx compresses 'text/html' by default.

Remove 'text/html' from the list of to compress mime-types. 'text/html'
is compressed by default and it would generate a warning:

  [warn] duplicate MIME type "text/html" in /etc/nginx/nginx.conf:28
Include more information in motd.

Add EC2 Instance ID, Public IP and Private IP to message of the day.
Enable other deploy providers.

Introduce default[:opsworks][:deploy_chef_provider] and
default[:deploy][application][:chef_provider] attributes, that allow the
customer to specify the deploy-provider. This enables use of Branch and
Revision Deploy-Provider.
Enable setting deploy provider per app.
Add support for Ruby 2.1
Fix literal include check.

Without the addition the check fails with 'invalid byte sequence in
US-ASCII'.