minor #8537 Docs re-org and removal of small sections (weaverryan)

This PR was squashed before being merged into the 2.7 branch (closes #8537).

Discussion
----------

Docs re-org and removal of small sections

Hi guys!

I'd like to have less "Guides" on the left. Some of them only have 1 article or (imo) are not something that's helpful for the user. In this PR, i:

1) Move Assetic out of the top-level and under `frontend`.
2) Removed/moved the Expressions guide
3) Removed/moved the "Request" guides

On Symfony.com, we would need to remove the "Assetic", "Expressions" and "Request" guides. All of this content still exists, just somewhere else.

The bigger goal is - through a number of PR's - to reduce the number of "guides" links and make sure we have the best links that people will be looking for.

Thanks!

Commits
-------

678a921 Docs re-org and removal of small sections

Author: weaverryan

_build/redirection_map

@@ -76,13 +76,20 @@
 /book/configuration /configuration
 /book/propel /propel/propel
 /book/performance /performance
-/cookbook/assetic/apply_to_option /assetic/apply_to_option
-/cookbook/assetic/asset_management /assetic/asset_management
-/cookbook/assetic/index /assetic
-/cookbook/assetic/jpeg_optimize /assetic/jpeg_optimize
-/cookbook/assetic/php /assetic/php
-/cookbook/assetic/uglifyjs /assetic/uglifyjs
-/cookbook/assetic/yuicompressor /assetic/yuicompressor
+/cookbook/assetic/apply_to_option /frontend/assetic/apply_to_option
+/cookbook/assetic/asset_management /frontend/assetic/asset_management
+/cookbook/assetic/index /frontend/assetic
+/cookbook/assetic/jpeg_optimize /frontend/assetic/jpeg_optimize
+/cookbook/assetic/php /frontend/assetic/php
+/cookbook/assetic/uglifyjs /frontend/assetic/uglifyjs
+/cookbook/assetic/yuicompressor /frontend/assetic/yuicompressor
+/assetic /frontend/assetic
+/assetic/apply_to_option /frontend/assetic/apply_to_option
+/assetic/asset_management /frontend/assetic/asset_management
+/assetic/jpeg_optimize /frontend/assetic/jpeg_optimize
+/assetic/php /frontend/assetic/php
+/assetic/uglifyjs /frontend/assetic/uglifyjs
+/assetic/yuicompressor /frontend/assetic/yuicompressor
 /cookbook/bundles/best_practices /bundles/best_practices
 /cookbook/bundles/configuration /bundles/configuration
 /cookbook/bundles/extension /bundles/extension
@@ -150,7 +157,8 @@
 /cookbook/event_dispatcher/event_listener /event_dispatcher
 /cookbook/event_dispatcher/index /event_dispatcher
 /cookbook/event_dispatcher/method_behavior /event_dispatcher/method_behavior
-/cookbook/expressions /expressions/expressions
+/cookbook/expressions /security/expressions
+/expressions /security/expressions
 /cookbook/form/create_custom_field_type /form/create_custom_field_type
 /cookbook/form/create_form_type_extension /form/create_form_type_extension
 /cookbook/form/data_transformers /form/data_transformers
@@ -181,10 +189,10 @@
 /cookbook/profiler/matchers /profiler/matchers
 /cookbook/profiler/profiling_data /profiler/profiling_data
 /cookbook/profiler/storage /profiler/storage
-/cookbook/psr7 /request/psr7
+/cookbook/psr7 /components/psr7
 /cookbook/request/index /request
-/cookbook/request/load_balancer_reverse_proxy /request/load_balancer_reverse_proxy
-/cookbook/request/mime_type /request/mime_type
+/cookbook/request/load_balancer_reverse_proxy /deployment/proxies
+/cookbook/request/mime_type /reference/configuration/framework#formats
 /cookbook/routing/conditions /routing/conditions
 /cookbook/routing/custom_route_loader /routing/custom_route_loader
 /cookbook/routing/debug /routing/debug
@@ -303,6 +311,7 @@
 /components/form/type_guesser /form/type_guesser
 /components/http_foundation/index /components/http_foundation
 /components/http_foundation/introduction /components/http_foundation
+/components/http_foundation/trusting_proxies /deployment/proxies
 /components/http_kernel/introduction /components/http_kernel
 /components/http_kernel/index /components/http_kernel
 /components/property_access/introduction /components/property_access
@@ -327,3 +336,4 @@
 /form /forms
 /testing/simulating_authentication /testing/http_authentication
 /validation/group_service_resolver /form/validation_group_service_resolver
+/request/load_balancer_reverse_proxy /deployment/proxies

best_practices/web-assets.rst

@@ -49,7 +49,7 @@ tools like GruntJS.
     Use Assetic to compile, combine and minimize web assets, unless you're
     comfortable with frontend tools like GruntJS.
 
-:doc:`Assetic </assetic/asset_management>` is an asset manager capable
+:doc:`Assetic </frontend/assetic/asset_management>` is an asset manager capable
 of compiling assets developed with a lot of different frontend technologies
 like LESS, Sass and CoffeeScript. Combining all your assets with Assetic is a
 matter of wrapping all the assets with a single Twig tag:
@@ -87,8 +87,8 @@ Learn More about Assetic
 ------------------------
 
 Assetic can also minimize CSS and JavaScript assets
-:doc:`using UglifyCSS/UglifyJS </assetic/uglifyjs>` to speed up your
-websites. You can even :doc:`compress images </assetic/jpeg_optimize>`
+:doc:`using UglifyCSS/UglifyJS </frontend/assetic/uglifyjs>` to speed up your
+websites. You can even :doc:`compress images </frontend/assetic/jpeg_optimize>`
 with Assetic to reduce their size before serving them to the user. Check out
 the `official Assetic documentation`_ to learn more about all the available
 features.

components/expression_language.rst

@@ -119,7 +119,6 @@ Learn More
     :maxdepth: 1
     :glob:
 
-    /expressions
     /components/expression_language/*
     /service_container/expression_language
     /reference/constraints/Expression

components/http_foundation.rst

@@ -611,7 +611,6 @@ Learn More
     /components/http_foundation/*
     /controller
     /controller/*
-    /request/*
     /session/*
     /http_cache/*
 

components/http_foundation/trusting_proxies.rst

@@ -7,7 +7,7 @@ Trusting Proxies
 .. tip::
 
     If you're using the Symfony Framework, start by reading
-    :doc:`/request/load_balancer_reverse_proxy`.
+    :doc:`/deployment/proxies`.
 
 If you find yourself behind some sort of proxy - like a load balancer - then
 certain header information may be sent to you using special ``X-Forwarded-*``

request/psr7.rst renamed to components/psr7.rst

@@ -13,7 +13,7 @@ Installation
 
 You can install the component in 2 different ways:
 
-* :doc:`Install it via Composer </components/using_components>` (`symfony/psr-http-message-bridge on Packagist <https://packagist.org/packages/symfony/psr-http-message-bridge>`_);
+* :doc:`Install it via Composer </components/using_components>` (`symfony/psr-http-message-bridge on Packagist`_);
 * Use the official Git repository (https://github.com/symfony/psr-http-message-bridge).
 
 The bridge also needs a PSR-7 implementation to allow converting HttpFoundation
@@ -87,3 +87,4 @@ to a :class:`Symfony\\Component\\HttpFoundation\\Response` instance::
 
 .. _`PSR-7`: http://www.php-fig.org/psr/psr-7/
 .. _`Zend Diactoros`: https://github.com/zendframework/zend-diactoros
+.. _`symfony/psr-http-message-bridge on Packagist`: https://packagist.org/packages/symfony/psr-http-message-bridge

request/load_balancer_reverse_proxy.rst renamed to deployment/proxies.rst

@@ -2,5 +2,11 @@ Front-end
 =========
 
 See the latest version of the docs for frontend tools. Or, see
-:doc:`/assetic`.
+:doc:`/frontend/assetic`.
 
+.. toctree::
+    :maxdepth: 1
+    :glob:
+    :hidden:
+
+    frontend/*