Update the documentation and publish the 2.10 version of Ansible documentation. Tasks include:

- [x] Remove 2.7 from the version switcher in conf.py in devel, stable-2.10, stable-2.9 and stable-2.8 and [2.9_ja](https://github.com/acozine/ansible/tree/japanese_2.9_to_prod) - see #64109

- [x] Get redirects in place for all old modules to new module-in-collection - https://github.com/ansible-community/antsibull/issues/77

- [x] Review changelogs in stable-2.10 for base and ansible

- [x] Backport autogenerated Ansible 2.10 porting guide to stable-2.10

- [x] Update 2.10 porting guide to point to stable-2.10

- [x] Update the Release Status grid on the Release and Maintenance page in devel and stable-2.10

- [x] Backport release Status grid to 2.9 and 2.8.

- [x] Update the version suggested for RHEL users in the installation docs, see https://github.com/ansible/ansible/pull/48173 

- [x] Backport the updated instructions for backporting to `latest`, see https://github.com/ansible/ansible/pull/56578

<del>Update the “too old” version number that suppresses the publication of “version_added” metadata older than a certain Ansible version, see https://github.com/ansible/ansible/pull/50097 </del> (no longer supported)

- [x] <del>Update the versions listed on the docs landing page - see https://github.com/ansible/docsite/pull/8 </del> removed these instead as it repeats the version switcher - https://github.com/ansible/docsite/pull/28

- [x] Update EOL banner on stable-2.7

- [x] Make sure all server-side redirects are updated as necessary - see https://github.com/ansible/docsite/pull/11 

- [x] Resolve latest vs 2.10 on docsite

- [x] Add skeleton roadmap for 2.11

- [x] <del>Add skeleton porting guide for 2.11</del> - porting guide for Ansible now autogenerated. ansible-base has a skeleton.

- [x] republish 2.10 on release day.

- [x]  post release - update intersphinx links.  see #66646 (should be done for ansible-base and Ansible releases)

- [x] post release (day or so later) - update sitemap for google. See https://github.com/ansible/docsite/pull/17

- [x]  post release reindex swiftype search (after sitemap is in place)

Future Releases - remove the release/maintenance page and porting guide pages from the new release when the branch is created and replace with stub page pointing up to the devel versions of these release-independent pages.

<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
docs.ansible.com
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below

```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. OS version, browser, etc. -->

##### ADDITIONAL INFORMATION
<!--- Describe how this improves the documentation, e.g. before/after situation or screenshots -->

<!--- HINT: You can paste gist.github.com links for larger files -->
"""Miscellaneous utility functions and classes."""
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
import contextlib
import errno
import fcntl
import inspect
import os
import pkgutil
import random
import re
import shutil
import socket
import stat
import string
import subprocess
import sys
import tempfile
import time
import zipfile
from struct import unpack, pack
from termios import TIOCGWINSZ
try:
    from abc import ABC
except ImportError:
    from abc import ABCMeta
    ABC = ABCMeta('ABC', (), {})
try: