Split documents per OS, fix few things, drop and add few OSes (#5328)

* Exclude include files from being built

* Split install guides into multiple documents (one per OS/version combo)

* Update references

* Unify anchor names

* Update pyenv requirements in CentOS 7 guide

* Update install guides for RHEL derivatives to not use pyenv

* Add guide for Rocky Linux 8

* 8.4+ -> 8.4-8.x

* Add 'the'

docs/install_guides/index.rst

@@ -0,0 +1,31 @@
+.. _install-guides:
+
+Installing Red
+==============
+
+The list below shows the installation guides available based on the operating system being used.
+
+If you want to host Red on a VPS and are unsure what operating system you should choose,
+we recommend **Ubuntu 20.04 LTS**.
+
+.. toctree::
+   :maxdepth: 1
+
+   windows
+   mac
+   arch
+   centos-7
+   centos-8
+   centos-stream-8
+   debian-10
+   debian-11
+   fedora
+   opensuse-leap-15
+   opensuse-tumbleweed
+   oracle-linux-8
+   raspberry-pi-os-10
+   rhel-8
+   rocky-linux-8
+   ubuntu-1804
+   ubuntu-2004
+   ubuntu-non-lts