* Full finalize the planned work for health checks of execution nodes
* Implementation of instance health_check endpoint
* Also do version conditional to node_type
* Do not use receptor mesh to check main cluster nodes health
* Fix bugs from testing health check of cluster nodes, add doc
* Add a few fields to health check serializer missed before
* Light refactoring of error field processing
* Fix errors clearing error, write more unit tests
* Update health check info in docs
* Bump migration of health check after rebase
* Mark string for translation
* Add related health_check link for system auditors too
* Handle health_check cluster node timeout, add errors for peer judgement
* Before, we had a special group, tower, that ran any async work that
tower needed done. This allowed users fine grain control over which
nodes did background work. However, this granularity was too complicated
for users. So now, all tower system work goes to a special non-user
exposed celery queue. Tower remains the fallback instance group to
execute jobs on. The tower group will be created upon install and
protected from deletion.
* related to https://github.com/ansible/ansible-tower/issues/7931
* The Tower Instance group is special. It should always exist, so
prevent any delete to it.
* Only allow super users to associate/disassociate instances the 'tower'
instance group.
* Do not allow fields of tower instance group to be changed.
This avoids re-loading objects from the database in our
chain of permission checking, wherever possible.
access.py is equiped to handle object references instead
of pk ints, and permissions.py is changed to pass those refs.
* New event types for stdout lines not associated with a callback event.
* New stdout, start_line, end_line and verbosity fields for job/ahc events.
* Callback plugins to wrap Ansible default/minimal stdout callbacks and embed callback event data using ANSI escape sequences.
* Callback plugin library to wrap ansible.display.Display class methods.
* Output filter to extract event data from stdout and create job/ahc events.
* Update stdout formats to strip new ANSI escape sequences.
