Remove mentions of Object.

Remove references to Object and the methods it provides.

Fixes #1278

en/appendices/3-0-migration-guide.rst

@@ -161,9 +161,11 @@ The config reader classes have been renamed:
 Object
 ------
 
-- ``Object::log()`` was removed from Object and added to the :php:trait:`Cake\\Log\\LogTrait` class.
-- ``Object::requestAction()`` was removed from Object and added to the
-  :php:trait:`Cake\\Routing\\RequestActionTrait`.
+The ``Object`` class has been removed. It formerly contained a grab bag of
+methods that were used in various places across the framework. The most useful
+of these methods have been extracted into traits. You can use the
+:php:trait:`Cake\\Log\\LogTrait` to access the ``log()`` method. The
+:php:trait:`Cake\\Routing\\RequestActionTrait` provides ``requestAction()``.
 
 Console
 =======

en/core-libraries/logging.rst

@@ -219,10 +219,10 @@ is to use the static :php:meth:`Cake\\Log\\Log::write()` method::
     Log::write('debug', 'Something did not work');
 
 The second is to use the log() shortcut function available on any
-class that extends ``Object``. Calling log() will internally call
+using the ``LogTrait`` Calling log() will internally call
 ``Log::write()``::
 
-    // Executing this inside a CakePHP class:
+    // Executing this inside a class using LogTrait
     $this->log("Something did not work!", 'debug');
 
 All configured log streams are written to sequentially each time

en/development/debugging.rst

@@ -162,22 +162,22 @@ Using Logging to Debug
 ======================
 
 Logging messages is another good way to debug applications, and you can use
-:php:class:`CakeLog` to do logging in your application. All objects that
-extend :php:class:`Object` have an instance method `log()` which can be used
+:php:class:`Cake\\Log\\Log` to do logging in your application. All objects that
+use ``LogTrait`` have an instance method `log()` which can be used
 to log messages::
 
     $this->log('Got here', 'debug');
 
 The above would write ``Got here`` into the debug log. You can use log entries
 to help debug methods that involve redirects or complicated loops. You can also
-use :php:meth:`CakeLog::write()` to write log messages. This method can be called
+use :php:meth:`Cake\\Log\\Log::write()` to write log messages. This method can be called
 statically anywhere in your application one CakeLog has been loaded::
 
-    // in app/Config/bootstrap.php
-    App::uses('CakeLog', 'Log');
+    // At the top of the file you want to log in.
+    use Cake\Log\Log;
 
-    // Anywhere in your application
-    CakeLog::write('debug', 'Got here');
+    // Anywhere that Log has been imported.
+    Log::debug('Got here');
 
 Debug Kit
 =========