We should rearrange Zulip's developer docs to make it easier to
find the documentation that new contributors need.
Name changes
Rename "Code contribution guide" section -> "Contributing to Zulip".
Rename "Contributing to Zulip" page -> "Contributing guide".
Organizational changes to the newly-named "Contributing to Zulip":
Move up "Contributing to Zulip", as the third link in sidebar index.
Move up renamed "Contributing guide" page to the top of this section.
Move up "Zulip code of Conduct", as the second link of this section.
Move down "Licensing", as the last link of this section.
Move "Accessibility" just below "HTML and CSS" in Subsystems section.
Update all links according to the changes above.
Redirects should be added as needed.
Fixes: #22517.
Updates the tutorial for writing help center articles to encourage
contributors to add to or enhance the existing help center docs
before writing a new articles for new features.
Also, generally updates references to 'user documentation' to be
'help center documentation'.
Additionally, updates some headers within the tutorials for clarity
and consistency, and adds some linkifying throughout the section on
writing documentation.
We recently changed /developer-community to /development-community.
Now that this change is in production, we can also migrate the
external links in our ReadTheDocs documentation.
David Rosa
Lauryn Menard
Eeshan Garg
Anders Kaseorg