- `delete` lets you delete a specific var under a specific generator;
- `delete_store` deletes an entire store.
The `delete` method could be useful to "garbage-collect" unused vars as
a machine's configuration changes.
The `delete_store` method can be used to delete all the vars for a
machine when the machine is deleted. The current behavior is to leave
everything behind.
Important point:
- `delete_store` needs to be idempotent because public and
"private"/"secret" vars for a machine can share the same physical
store (directory), and deleting either type of store (public or
private) will delete both.
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