Upgrade the support for Open Badges 2 to support a real open badges 2 backpack.
Moodle can only talk to one backpack at a time, so after switching backpacks, users
will have to manually disconnect and then reconnect their backpack to the new one.
This commit combines several changes:
* Split classes into badges namespace
* Publish expiry data with a badge
* Publish badge alignments in badges exported to the backpack.
* Export the criteria for a badge to the backpack.
The badges feature allows to integrate Mozilla "Open Badges" to issue, assign,
manage and display digital badges in Moodle. This feature supports:
-- badge creation and issuing based on criteria
-- badge baking and verification service
-- direct pushing of internal badges to external backpack
-- interanl and external badge display in Moodle
-- Moodle block to display latest badges
Damyon Wiese