Revert "Bug fixes for the folder watcher. Recurse for directories. Append only files. Skip only for files"

This reverts commit fedc67f94bb5f7732cf9272635734351e2877ca5.
Revert "Use the file hash instead of the last modification time"

This reverts commit 4c47f1e4aff8e24ec686c650ff050c6985478d54.
Bug fix for the folder watcher: The folder watcher did not recurse properly because the skipFile expression was evaluated for folders.