[2.1.6] More meaningful error messages and key figures for iCloud Sync

Currently, possible error messages for iCloud Sync sometimes only display the status codes and are not very meaningful (e.g. CKErrorCode 7 with too many requests). This should be changed and an error message including a solution should be displayed instead.

In addition, the more detailled overview of the current sync status under the ‘Show more’ button should be expanded, e.g. to display the transactions on the device and in the iCloud to enable quick comparison.

Result: