Add some tests for Engine::Settings
user
```ruby
# -*- coding: utf-8 -*-

require 'simplecov'
require 'simplecov-rcov'
require 'logger'
require 'coveralls'

Coveralls.wear!
SimpleCov.formatter = SimpleCov::Formatter::MultiFormatter[
  SimpleCov::Formatter::RcovFormatter,
  Coveralls::SimpleCov::Formatter
]
SimpleCov.command_name 'bacon'
SimpleCov.start do
  add_filter '/vendor/'
  add_filter '/spec/'
end

require 'digest/sha1'
require_relative '../lib/diversity'

describe 'Engine::Settings' do
  should 'Return a correct list of angulars' do
    registry_path = File.expand_path(
      File.join(File.dirname(__FILE__), 'components')
    )
    registry = Diversity::Registry::Local.new(base_path: registry_path, base_url: 'https://dummy.domain/components')
    engine = Diversity::Engine.new(registry: registry)
    comp = registry.get_component('weak-sauce')
    engine.render(comp)
    angular = engine.send(:settings).angular
    angular.length.should.equal(1)
    angular[0].should.equal('dummy')
  end

  should 'Return a correct list of scripts' do
    registry_path = File.expand_path(
      File.join(File.dirname(__FILE__), 'components')
    )
    registry = Diversity::Registry::Local.new(base_path: registry_path, base_url: 'https://dummy.domain/components')
    engine = Diversity::Engine.new(registry: registry)
    comp = registry.get_component('weak-sauce')
    engine.render(comp)
    scripts = engine.send(:settings).scripts
    scripts.length.should.equal(3)
    scripts.uniq.length.should.equal(3)
    scripts[0].should.equal('https://dummy.domain/components/dummy/0.0.1/js/dummy1.js')
    scripts[1].should.equal('https://dummy.domain/components/dummy/0.0.1/js/dummy2.js')
    scripts[2].should.equal('https://dummy.domain/components/weak-sauce/0.0.4/weak_sauce.js')
  end

  should 'Return a correct list of styles' do
    registry_path = File.expand_path(
      File.join(File.dirname(__FILE__), 'components')
    )
    registry = Diversity::Registry::Local.new(base_path: registry_path, base_url: 'https://dummy.domain/components')
    engine = Diversity::Engine.new(registry: registry)
    comp = registry.get_component('weak-sauce')
    engine.render(comp)
    styles = engine.send(:settings).styles
    styles.length.should.equal(1)
    styles[0].should.equal('https://dummy.domain/components/dummy/0.0.1/css/dummy.css')
  end
end
```
assistant