docs: Prepare for new sub tree

See #11925

docs/content/en/quick-reference/_index.md

@@ -1,16 +0,0 @@
----
-title: Quick reference guides
-linkTitle: Overview
-description: Quick reference guides to Hugo's features, functions, and methods.
-categories: []
-keywords: []
-menu:
-  docs:
-    identifier: quick-reference-overview
-    parent: quick-reference
-    weight: 10
-weight: 10
-showSectionMenu: false
----
-
-Quick reference guides to Hugo's features, functions, and methods.

docs/content/en/quick-reference/functions.md

@@ -1,14 +0,0 @@
----
-title: Functions
-description: A quick reference guide to Hugo's functions, grouped by namespace. Aliases, if any, appear in parentheses to the right of the function name.
-categories: [quick reference]
-keywords: []
-menu:
-  docs:
-    parent: quick-reference
-    weight: 30
-weight: 30
-toc: true
----
-
-{{% quick-reference section="functions" %}}

docs/content/en/quick-reference/methods.md

@@ -1,14 +0,0 @@
----
-title: Methods
-description: A quick reference guide to Hugo's methods, grouped by object.
-categories: [quick reference]
-keywords: []
-menu:
-  docs:
-    parent: quick-reference
-    weight: 40
-weight: 40
-toc: true
----
-
-{{% quick-reference section="methods" %}}

docs/content/en/quick-reference/page-collections.md

@@ -1,46 +0,0 @@
----
-title: Page collections
-description: A quick reference guide to Hugo's page collections.
-categories: [quick reference]
-keywords: []
-menu:
-  docs:
-    parent: quick-reference
-    weight: 50
-weight: 50
-toc: true
----
-
-## Page
-
-Use these `Page` methods when rendering lists on [section] pages, [taxonomy] pages, [term] pages, and the home page.
-
-[section]: /getting-started/glossary/#section
-[taxonomy]: /getting-started/glossary/#taxonomy
-[term]: /getting-started/glossary/#term
-
-{{< list-pages-in-section path=/methods/page filter=methods_page_page_collections filterType=include omitElementIDs=true titlePrefix=PAGE. >}}
-
-## Site
-
-Use these `Site` methods when rendering lists on any page.
-
-{{< list-pages-in-section path=/methods/site filter=methods_site_page_collections filterType=include omitElementIDs=true titlePrefix=SITE. >}}
-
-## Filter
-
-Use the [`where`] function to filter page collections.
-
-[`where`]: /functions/collections/where
-
-## Sort
-
-Use these methods to sort page collections.
-
-{{< list-pages-in-section path=/methods/pages filter=methods_pages_sort filterType=include titlePrefix=. omitElementIDs=true titlePrefix=PAGES. >}}
-
-## Group
-
-Use these methods to group page collections.
-
-{{< list-pages-in-section path=/methods/pages filter=methods_pages_group filterType=include titlePrefix=. omitElementIDs=true titlePrefix=PAGES. >}}