Syncthing can report an "idle" status despite pull errors. This still means
the directory is out-of-sync. With this change the out-of-sync status is
only cleared when reading a "FolderSummary" event without pull errors (or
temporarily if the directory is e.g. scanning).
* Show the raw directory status from the Syncthing API if
it is an unknown (maybe newly introduced) status value.
* Note that the same does not apply to the device status
because the device status is only deduced from other
information.
* Rely not only on the FolderErrors event
* Request pull errors when opening the dialog
* Use "pullErrors" from FolderSummary
* Move code for directory error dialog into
its own class
This should fix that sometimes obsolete errors
were still displayed or actually present errors
missing.
* Discard folder errors older than the last "sync" state
* Unfortunately we don't know the the time of the last
sync from the beginning. To prevent showing obsolete
errors in this state, discard all errors if the status
changes to something other than "out-of-syn".