This contains the following behavioral changes:
- Duplicate folder IDs is now fatal during startup
- Invalid folder flags in the ClusterConfig is fatal for the connection
(this will go away soon with the proto changes, as we won't have any
unknown flags any more then)
- Empty path is a folder error reported at runtime
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3370
The various path cleaning operations done in in cleanedPath() removes
it, so we make sure it's added again at the end. This makes adding the
slash in prepare() unnecessary, but keep it anyway for display purposes
(people looking at the config).
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3342
The VersioningConfig change is because it defaults to nil but gets
deserialized to map[string]string{}. Now prepare() enforces a single
representation of the empty map.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3065
