Support alias when importing from containers

[marian13]

• Current DependencyContainer implementation violates the Open/Closed principle and smells like Incomplete Library Code.

• That is why we should add an ability to specify aliases like so:

  module FirstFeature
    module Container
      include ConvenientService::DependencyContainer::Export
  
      export :hello do
        puts "hello from `FirstFeature`"
      end
    end
  end
  
  module SecondFeature
    module Container
      include ConvenientService::DependencyContainer::Export
  
      export :hello do
        puts "hello from `SecondFeature`"
      end
    end
  end
  
  class User
    include ConvenientService::DependencyContainer::Import
  
    import :hello, as: :"first_feature.hello", from: FirstFeature::Container
  
    import :hello, as: :"second_feature.hello", from: SecondFeature::Container
  end
  
  user = User.new
  
  user.first_feature.hello
  
  user.second_feature.hello

[Olha-30]

@marian13 I completely agree 😄 I'll take a look