Dummy placeholder for changes in 6.4

Source commit: 96a80558b57a36db6bfe1eb8df403434b609d14e

source/resource/Propagation.rc

@@ -94,4 +94,6 @@ BEGIN
   NEW_6_2_HOST_CERTIFICATES, "Support for OpenSSH certificates for host verification"
   NEW_6_2_SYNC_HASH, "File hash can be used as criterion for synchronization"
   NEW_6_2_MOVE_DUPLICATE, "Improved behaviour when moving and duplicating remote files"
+
+  NEW_6_4, "TODO"
 END