Use Sidekiq.logger when Sidekiq::Logging is unavailable (reidmorrison#95)

* use Sidekiq.logger when Sidekiq::Logging is unavailable

* always use Sidekiq.logger

Author: bobvanderlinden

lib/rails_semantic_logger/engine.rb

@@ -108,7 +108,7 @@ class Engine < ::Rails::Engine
       Resque.logger           = SemanticLogger[Resque] if defined?(Resque) && Resque.respond_to?(:logger)
 
       # Replace the Sidekiq logger
-      Sidekiq::Logging.logger = SemanticLogger[Sidekiq] if defined?(Sidekiq)
+      Sidekiq.logger = SemanticLogger[Sidekiq] if defined?(Sidekiq)
 
       # Replace the Sidetiq logger
       Sidetiq.logger          = SemanticLogger[Sidetiq] if defined?(Sidetiq)