Added a new storage type (ucan)
Implemented a new storage type to provide more options.
Improved flexibility of keyMaterial in Base
The keyMaterial setting in Base can now be changed later, allowing for smoother storage addition.
Fixed history upload issue for new storages
Resolved a problem where history was not being uploaded to newly added storages if there was no header for them.
Introduced makeCarSince() method to Sync class
This new method helps create encrypted car files based on database, key material, and array of cids sinceClock, for smoother synchronization.
Test for changes API call on rest storage type
Added a test to ensure proper functioning of changes API call for the rest storage type.
This is a first pass at implementing changes-diffs to the cloud.