added cookbook to automate package installation via cookbook attributes

Description of your patch
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Adds a cookbook to automate package installation.  Package names and versions are specified as hashes in the attributes file.

Estimated risk
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zero, the require_package is commented out in the main recipe

Components involved
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emerge cookbook

Description of testing done
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tested with examples in cookbook on personal instance

QA Instructions
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uncomment require_recipe "packages" in main recipe, upload and apply to instance