[Migrate]: BP_User_Query

[imath]

Link to the existing BP Codex page.

https://codex.buddypress.org/developer/bp_user_query/

What needs to be done?

This API is very important in BuddyPress, the current codex page explains it a bit, but I believe it needs an important work to explain how to use it, why developers should stop using the deprecated BP_Core_User::get_users() method, how to extend it, how other components are extending it, etc..

Handbook to migrate the page in

buddypress/docs/developer

Tasks to accomplish

• This task has been added to the "Todo" panel of the Documentation project.
• The corresponding line of the data/README.md Pages list has been marked as "Migrate issue/task created".
• A PR has been submitted to the BuddyPress GH repository, it has been linked to this issue/task & the task was moved to the "In progress" panel of the Documentation project.
• The PR has been converted to a SVN patch and committed to the BuddyPress SVN repository & the task was moved to the "Done" panel of the Documentation project.