minor #13706 Removed ClassLoader, DotEnv, Mercure, WebLink, Templating, ErrorHandler and Polyfill component docs (wouterj)

This PR was squashed before being merged into the 4.4 branch.

Discussion
----------

Removed ClassLoader, DotEnv, Mercure, WebLink, Templating, ErrorHandler and Polyfill component docs

Let's take a bigger step and remove some more docs. These components were some more easy picks.

The polyfills are already listed in https://symfony.com/components and their README files describe the polyfills contained in each package already. So I think we can remove them without any other change.

Commits
-------

522d63b Removed ClassLoader component docs
386625b Removed ErrorHandler component docs
9d2313b Removed Templating component docs
1079fe3 Removed WebLink component docs
6bb1587 Removed Polyfill component docs
9943aae Removed Mercure component docs
4bc7793 Removed DotEnv component docs

Author: wouterj

_build/redirection_map

@@ -13,7 +13,7 @@
 /cookbook/email /email
 /cookbook/gmail /cookbook/email/gmail
 /cookbook/console /components/console
-/cookbook/tools/autoloader /components/class_loader
+/cookbook/tools/autoloader https://github.com/symfony/class-loader
 /cookbook/tools/finder /components/finder
 /cookbook/service_container/parentservices /service_container/parent_services
 /cookbook/service_container/factories /service_container/factories
@@ -295,15 +295,15 @@
 /components/asset/introduction /components/asset
 /components/browser_kit/index /components/browser_kit
 /components/browser_kit/introduction /components/browser_kit
-/components/class_loader/introduction /components/class_loader
-/components/class_loader/index /components/class_loader
-/components/class_loader/cache_class_loader /components/class_loader
-/components/class_loader/class_loader /components/class_loader
-/components/class_loader/class_map_generator /components/class_loader
-/components/class_loader/debug_class_loader /components/class_loader
-/components/class_loader/map_class_loader /components/class_loader
-/components/class_loader/map_class_loader /components/class_loader
-/components/class_loader/psr4_class_loader /components/class_loader
+/components/class_loader/introduction https://github.com/symfony/class-loader
+/components/class_loader/index https://github.com/symfony/class-loader
+/components/class_loader/cache_class_loader https://github.com/symfony/class-loader
+/components/class_loader/class_loader https://github.com/symfony/class-loader
+/components/class_loader/class_map_generator https://github.com/symfony/class-loader
+/components/class_loader/debug_class_loader https://github.com/symfony/class-loader
+/components/class_loader/map_class_loader https://github.com/symfony/class-loader
+/components/class_loader/map_class_loader https://github.com/symfony/class-loader
+/components/class_loader/psr4_class_loader https://github.com/symfony/class-loader
 /components/config/introduction /components/config
 /components/config/index /components/config
 /components/console/helpers/tablehelper /components/console/helpers/table
@@ -350,10 +350,10 @@
 /components/routing/hostname_pattern /routing/hostname_pattern
 /components/security/introduction /components/security
 /components/security/index /components/security
-/components/templating/introduction /components/templating
-/components/templating/index /components/templating
-/components/templating/helpers/assetshelper /components/templating/assetshelper
-/components/templating/helpers/slotshelper /components/templating/slotshelper
+/components/templating/introduction https://github.com/symfony/templating
+/components/templating/index https://github.com/symfony/templating
+/components/templating/helpers/assetshelper https://github.com/symfony/templating
+/components/templating/helpers/slotshelper https://github.com/symfony/templating
 /components/translation/introduction /components/translation
 /components/translation/index /components/translation
 /components/var_dumper/introduction /components/var_dumper
@@ -399,7 +399,7 @@
 /security/acl_advanced /security/acl
 /security/password_encoding /security
 /weblink /web_link
-/components/weblink /components/web_link
+/components/weblink https://github.com/symfony/web-link
 /frontend/encore/installation-no-flex /frontend/encore/installation
 /http_cache/form_csrf_caching /security/csrf
 /console/logging /console
@@ -481,3 +481,25 @@
 /components/routing https://github.com/symfony/routing
 /doctrine/pdo_session_storage /session/database
 /doctrine/mongodb_session_storage /session/database
+/components/dotenv https://github.com/symfony/dotenv
+/components/mercure https://github.com/symfony/mercure
+/components/polyfill_apcu https://github.com/symfony/polyfill-apcu
+/components/polyfill_ctype https://github.com/symfony/polyfill-ctype
+/components/polyfill_iconv https://github.com/symfony/polyfill-iconv
+/components/polyfill_intl_grapheme https://github.com/symfony/polyfill_intl-grapheme
+/components/polyfill_intl_icu https://github.com/symfony/polyfill_intl-icu
+/components/polyfill_intl_idn https://github.com/symfony/polyfill_intl-idn
+/components/polyfill_intl_normalizer https://github.com/symfony/polyfill_intl-normalizer
+/components/polyfill_mbstring https://github.com/symfony/polyfill-mbstring
+/components/polyfill_php54 https://github.com/symfony/polyfill-php54
+/components/polyfill_php55 https://github.com/symfony/polyfill-php55
+/components/polyfill_php56 https://github.com/symfony/polyfill-php56
+/components/polyfill_php70 https://github.com/symfony/polyfill-php70
+/components/polyfill_php71 https://github.com/symfony/polyfill-php71
+/components/polyfill_php72 https://github.com/symfony/polyfill-php72
+/components/polyfill_php73 https://github.com/symfony/polyfill-php73
+/components/polyfill_uuid https://github.com/symfony/polyfill-uuid
+/components/web_link https://github.com/symfony/web-link
+/components/templating https://github.com/symfony/templating
+/components/error_handler https://github.com/symfony/error-handler
+/components/class_loader https://github.com/symfony/class-loader

components/asset.rst

@@ -401,6 +401,6 @@ Learn more
 ----------
 
 * :doc:`How to manage CSS and JavaScript assets in Symfony applications </frontend>`
-* :doc:`WebLink component </components/web_link>` to preload assets using HTTP/2.
+* :doc:`WebLink component </web_link>` to preload assets using HTTP/2.
 
 .. _`Webpack`: https://webpack.js.org/