re-factoring for 1.3: /lib, /models, /concerns, /services, Rails 3 syntax, other code cleanup 

* All tests pass after each commit
* Move files are in separate commits from edit files
* Best to view without whitespace changes https://github.com/theforeman/foreman/pull/765/files?w=1
* Best to review one commit at a time
* Net & Proxy features remain in /lib per @ohadlevy