Fixes #2439 - Add true to respond_to? calls for initialize_puppetca
fixes #2440 remove unused code and files
fixes #2411 move files to new location /models/concerns /controllers/concersns /services /mailers /observers
fixes #2411 added ActiveSupport::Concerns to mixins
fixes #2411 remove unnecessary require statements in controllers
fixes #2411 refactor config/initializers
fixes #2443 move STI model to separate folders