Feature request: add a flag for merging local changes to remote, instead of sync-ing

There should be a flag for apply command (called --merge), or a new command (called 'merge'), to allow you to merge local changes with the existing remote configuration, without deleting remote parameters which don't exist locally.
So if you have a parameter that has changed value locally, it will change to remote as well.
But if there's a remote parameter which you don't have locally, it should not delete from remote.