[nexus-artifact] initial commit of nexus-artifact cookbook
[signifyd-platform] initial commit of signifyd-platform cookbook
[nexus-artifact] add librarian files to chefignore
update gitignore to exclude selected files under site-cookbooks
add chef-sugar and nexus_cli to top-level Gemfile for unit testing
[nexus-artifact] remove superfluous Gemfile
add top-level rubocop config
[cloudformation] adding platform-from-nexus template
add signifyd-platform role
[signifyd-platform] remove empty serverspec tests for now
[signifyd-platform] remove unused templates
Merge pull request #17 from signifyd/feature/platform-from-nexus

Add cookbooks, role and cloudformation template to support deploying Platform from Nexus