Fixes restoring of documents in a clustered index.

Changed

• BREAKING: UPDATE method no longer receives upsert query param
• BREAKING: Added UPSERT method
• BREAKING: Removed MERGE and STORE methods
• Restore always commits at the end

Fixed

• Restoring of documents in a clustered index
• Commit in databases with remote shards (remote wasn’t receiving the commit)
• Better handling of database flags (when changed)
• Uncompressed UUIDs representation was buggy