Remove some small email articles

Author: javiereguiluz

_build/redirection_map

@@ -150,10 +150,10 @@
 /cookbook/doctrine/registration_form /doctrine/registration_form
 /cookbook/doctrine/resolve_target_entity /doctrine/resolve_target_entity
 /cookbook/doctrine/reverse_engineering /doctrine/reverse_engineering
-/cookbook/email/cloud /email/cloud
+/cookbook/email/cloud /email
 /cookbook/email/dev_environment /email/dev_environment
 /cookbook/email/email /email
-/cookbook/email/gmail /email/gmail
+/cookbook/email/gmail /email
 /cookbook/email/index /email
 /cookbook/email/spool /email/spool
 /cookbook/email/testing /email/testing
@@ -348,6 +348,8 @@
 /components/yaml/index /components/yaml
 /deployment/tools /deployment
 /install/bundles /setup/bundles
+/email/gmail /email
+/email/cloud /email
 /event_dispatcher/class_extension /event_dispatcher
 /form /forms
 /form/use_virtual_forms /form/inherit_data_option

email.rst

@@ -37,9 +37,6 @@ environment variable in the ``.env`` file:
     # use this to disable email delivery
     MAILER_URL=null://localhost
 
-    # use this to send emails via Gmail (don't use this in production)
-    MAILER_URL=gmail://username:password@localhost
-
     # use this to configure a traditional SMTP server
     MAILER_URL=smtp://localhost:25?encryption=ssl&auth_mode=login&username=&password=
 
@@ -107,15 +104,56 @@ The ``$message`` object supports many more options, such as including attachment
 adding HTML content, and much more. Refer to the `Creating Messages`_ section
 of the Swift Mailer documentation for more details.
 
+Using Gmail to Send Emails
+--------------------------
+
+During development, you might prefer to send emails using Gmail instead of
+setting up a regular SMTP server. To do that, update the ``MAILER_URL`` of your
+``.env`` file to this:
+
+.. code-block:: bash
+
+    # username is your full Gmail or Google Apps email address
+    MAILER_URL=gmail://username:password@localhost
+
+The ``gmail`` transport is simply a shortcut that uses the ``smtp`` transport,
+``ssl`` encryption, ``login`` auth mode and ``smtp.gmail.com`` host. If your app
+uses other encryption or auth mode, you must override those values
+(:doc:`see mailer config reference </reference/configuration/swiftmailer>`):
+
+.. code-block:: bash
+
+    # username is your full Gmail or Google Apps email address
+    MAILER_URL=gmail://username:password@localhost?encryption=tls&auth_mode=oauth
+
+If your Gmail account uses 2-Step-Verification, you must `generate an App password`_
+and use it as the value of the mailer password. You must also ensure that you
+`allow less secure apps to access your Gmail account`_.
+
+Using Cloud Services to Send Emails
+-----------------------------------
+
+Cloud mailing services are a popular option for companies that don't want to set
+up and maintain their own reliable mail servers. In Symfony apps, using these
+services is as simple as updating the value of ``MAILER_URL`` in the ``.env``
+file. For example, for `Amazon SES`_ (Simple Email Service):
+
+.. code-block:: bash
+
+    # The host will be different depending on your AWS zone
+    # The username/password credentials are obtained from the Amazon SES console
+    MAILER_URL=smtp://email-smtp.us-east-1.amazonaws.com:587?encryption=tls&username=YOUR_SES_USERNAME&password=YOUR_SES_PASSWORD
+
+Use the same technique for other mail services, as most of the time there is
+nothing more to it than configuring an SMTP endpoint.
+
 Learn more
 ----------
 
 .. toctree::
     :maxdepth: 1
 
     email/dev_environment
-    email/gmail
-    email/cloud
     email/spool
     email/testing
 
@@ -125,3 +163,5 @@ Learn more
 .. _`Mandrill`: https://mandrill.com/
 .. _`SendGrid`: https://sendgrid.com/
 .. _`Amazon SES`: http://aws.amazon.com/ses/
+.. _`generate an App password`: https://support.google.com/accounts/answer/185833
+.. _`allow less secure apps to access your Gmail account`: https://support.google.com/accounts/answer/6010255