Enables co-locating multiple tasks in a given work-set.
Tasks are bucketed by the following:
* OS
* job id
* setup container
* VM SKU & image (used in pre-1.0 style tasks)
* pool name (used in 1.0+ style tasks)
* if the task needs rebooting after the task setup script executes.
Additionally, a task will end up in a unique bucket if any of the following are true:
* The task is set to run on more than one VM
* The task is missing the `task.config.colocate` flag (all tasks created prior to this functionality) or the value is False
This updates the libfuzzer template to make use of colocation. Users can specify co-locating all of the tasks *or* co-locating the secondary tasks.
