Apply capacity algorithm changes

* This also adds fields to the instance view for tracking cpu and
  memory usage as well as information on what the capacity ranges are
* Also adds a flag for enabling/disabling instances which removes them
  from all queues and has them stop processing new work
* The capacity is now based almost exclusively on some value relative
  to forks
* capacity_adjustment allows you to commit an instance to a certain
  amount of forks, cpu focused or memory focused
* Each job run adds a single fork overhead (that's the reasoning
  behind the +1)

awx/main/models/inventory.py

@@ -1602,7 +1602,7 @@ class InventoryUpdate(UnifiedJob, InventorySourceOptions, JobNotificationMixin,
 
     @property
     def task_impact(self):
-        return 50
+        return 1
 
     # InventoryUpdate credential required
     # Custom and SCM InventoryUpdate credential not required