Added an article about private console commands

Author: javiereguiluz

console/private_commands.rst

@@ -0,0 +1,34 @@
+Creating Private Console Commands
+=================================
+
+Console commands are public by default, meaning that they are listed alongside
+other commands when executing the console application script without arguments
+or when using the ``list`` command.
+
+However, sometimes commands are not intended to be executed by end-users; for
+example, commands for the legacy parts of the application, commands exclusively
+executed through scheduled tasks, etc.
+
+In those cases, you can define the command as **private** setting the
+``setPublic()`` method to ``false`` in the command configuration::
+
+    // src/AppBundle/Command/FooCommand.php
+    namespace AppBundle\Command;
+
+    use Symfony\Component\Console\Command\Command;
+
+    class FooCommand extends Command
+    {
+        protected function configure()
+        {
+            $this
+                ->setName('app:foo')
+                // ...
+                ->setPublic(false)
+            ;
+        }
+    }
+
+Private commands behave the same as public commands and they can be executed as
+before, but they are no longer displayed in command listings, so end-users are
+not aware of their existence.