Add typical Syncthing files to default exclusion

For increasing default interoperability between Syncthing & Nextcloud if users may want to sync a (sub-)directory with both tools without thinking about that those hidden files synced by Nextcloud might break Syncthing

Signed-off-by: Felix Stupp <felix.stupp@banananet.work>

sync-exclude.lst

@@ -42,6 +42,11 @@ System Volume Information
 *.unison
 .nfs*
 
+# (default) metadata files created by Syncthing
+.stfolder
+.stignore
+.stversions
+
 My Saved Places.
 
 \#*#