* For >=5.68, we expect 'civicrm_queue.runner' to be deprecated.
* For >=5.68, we should use 'civicrm_queue.agent' instead
* For <5.68, we must still use 'civicrm_queue.runner'
* This also allows admins to improvise on queries

#2 Update composer

See merge request !3

The defaults that work well for production don't work well for debugging.
Add a short-hand for using more debug-oriented options.

Multiple updates, esp: Use "run as" property to manage workers

See merge request !2

* At NOTICE level, you should see 1-2 messages whenever there's an actual task to work on
* At INFO level (`-v`), you should see setup/teardown records for each major component (control channel, pool, pool-members)
* At DEBUG level (`-vv`), you should see detailed I/O

== Background

The "PipePool" has named "contexts".  Workers are restricted to only running
tasks for one context.  (If you need to run tasks in a new context, then you
need a new worker.)

The "CRM_Queue_Task" has the notion of "run as" -- where you specify who
should execute the task; eg "contact=100,domain=1".

== Before

Identities are not used.  All tasks are assigned to the same context, even
if they have different identities.

== After

The "run as" data is used to assign the "context" name, eg

* Task definition: "runAs = [contactId=>100, domainId=>1]"
* Context name: "c=100,d=1"

Thus, tasks will different identities will always be handled by different workers.

FIXME: when starting a worker, we need to set the active identity.