Dispute Kits data structure simplification #1357
Description
Follow up on #17 which turns out to be too complicated and error-prone.
Changes
- No more hierarchy of DK, we only have an array with no parent/children relationship
- DisputeKitClassic must be supported by every courts
- DisputeKitClassic cannot be disabled
- DisputeKitClassic is the fallback when the new court (after a court jump) doesn't support the current DK.