Ability to match multiple elements in an array

[aeijdenberg]

We would find it useful to be able to apply a replace pattern to all elements in an array.

For example:

- type: replace
  path: /instance_groups/*/vm_extensions?/-
  value: foo

This would be not be allowed as the last element - only as an intermediate one, and is only valid for the replace and remove operations.

[dsabeti]

Another use case for this: cf-deployment has some ops-files that change configuration for all instance groups in a deployment. For example, our ops-file for renaming the BOSH network updates each instance group to use a different network name.

When a new instance group gets added -- in cf-deployment, or because of an ops-file -- it's easy to forget to update the ops-file to change the new instance group. In fact, we had to implement this fix recently to rename the network for a new instance group. Because we forgot to do this change in the same release that added the adapter instance group, some operators experienced downtime when they deployed.

If we had wildcards in ops-file, we could completely avoid this problem and add instance groups more easily.