Log successful and failed login attempts in a separate log file

We log the login parameter and the request IP address.

Quoting the ENS:

> [op.acc.5.r5.1] Se registrarán los accesos con éxito y los fallidos.

lib/authentication_logger.rb

@@ -0,0 +1,24 @@
+class AuthenticationLogger
+  @loggers = {}
+
+  class << self
+    def log(message)
+      logger.info(message)
+    end
+
+    def path
+      Rails.root.join("log", Tenant.subfolder_path, "authentication.log")
+    end
+
+    private
+
+      def logger
+        @loggers[Apartment::Tenant.current] ||= build_logger
+      end
+
+      def build_logger
+        FileUtils.mkdir_p(File.dirname(path))
+        ActiveSupport::TaggedLogging.new(ActiveSupport::Logger.new(path, level: :info))
+      end
+  end
+end