* identity: Ensure state is changed on activation
This PR introduces some changes to the way activation flags are
processed in Vault.
Rather than reaching into subsystems and modifying
state from the activationflags package, each plugin can now register its
own ActivationFunc. Updates to activation flags now trigger the the
feature's ActivationFunc, which can encapsulate the associated
subsystem state.
We include a few bugfixes and minor cosmetic changes, like updates to
log lines and godocs.
* Check for nil system backend
* Move deduplication activation to common file
* Add identity dedup activation log lines
* Make interface methods clearer
* Clean up some comments
* More cleanups
* fixup! More cleanups
* fixup! More cleanups
6d5759ecb3