Override to_h to call to_hash method.

[mikenairn]

Fixes an issue where to_h returns nil instead of a hash.

irb(main):003:0> require 'cheffish'
irb(main):004:0> mc = Cheffish::MergedConfig.new
irb(main):005:0> mc.to_h
=> nil

ruby --version
ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-darwin12.5.0]

Prevents aws local balancer creation from working properly https://github.com/chef/chef-provisioning-aws/blob/master/lib/chef/provisioning/aws_driver/driver.rb#L123

[chef-supermarket]

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• @mikenairn

Please sign the CLA here.

[chef-supermarket]

Hi. Your friendly Curry bot here. Just letting you know that all commit authors have become authorized to contribute. I have added the "Signed CLA" label to this issue so it can easily be found in the future.

[lamont-granquist]

sort of feel the same way that this should just be a Chef::Mash, but it is super-simple so 👍