How to cache only metadata on Cache remote?

[ncw (Nick Craig-Wood)]

@thestigma

Nick has indicated that he has several large changes coming down the road for the VFS - which (according to my understanding) will include persistence in some things like the "upload-list"

This is my 3 point plan

Goals in order

1. Enable async writeback in a secure way
2. Enable --vfs-cache-mode full not to download the entire file immediately
3. Persistent metadata caching

I'm working on 1&2 at the moment which are related. 3 needs a bit more work but it isn't nearly as tricky!