Saving configuration on Anki objects

Transition to configuration on the Anki deck object

This update brings many more improvements:

* When cloning deck options, Straight Reward setting will be correctly
cloned along

* Straight Reward settings will be correctly export to .apkg files and reapplied when importing

* Configuration via meta.json is phased out

* Use modern Anki API for saving configurations

* Experimental support for multiple reviews on same card via sync hook