* config: singular ANSIBLE_COLLECTIONS_PATH
Every other *_PATH setting in ansible is singular, and the traditional
$PATH variable is also singular despite containing a list of
directories. Let's be consistent both internally and with POSIX
tradition.
* update all ANSIBLE_COLLECTIONS_PATHS env references to be singular
* deprecate plural ANSIBLE_COLLECTIONS_PATHS setting
* Inventory CLI - Ignore settings for when vars plugins should run and just always run them
* Add note to porting guide
* Fix loading vars plugins
* changelog
* Remove a staging test for ansible-inventory since it ignores that setting
* Move var plugins handling to a separate file
* Allow var plugins to require whitelisting
* Add global configuration ('demand', 'start') for users to control when they execute
* Add 'stage' configuration ('all', 'task', 'inventory') for users to control on a per-plugin basis when they execute
* Update ansible-inventory and InventoryManager to the global and stage configuration
* Update host_group_vars to use stage configuration and whitelisting
* Add documentation for using new options and to the developer's guide
* Add integration tests to exercise whitelisting and the new configuration options, using vars plugins in collections, and maintain backward compatibility
* Changelog
Co-Authored-By: Brian Coca <brian.coca+git@gmail.com>
Co-Authored-By: Sandra McCann <samccann@redhat.com>
